I am Sridhar Iyer, one of the faculty in Department of Computer Science. Also work with the interdisciplinary program on education technology which is a four year old department at IIT. For about ten years I worked in the area of networking and had about five PhD students do their thesis in networking and over the past three years I have stopped doing networking and do mostly education technology nowadays. So what I am going to be talking about in today's session is one strategy of how to get students engaged in the classroom and how to get them also learn better. So the strategy is called think-pair-share before we get into it. So let's ask the question that when we talk about MOOCs and blended classrooms we have this idea of creating videos and we'll put out videos, we'll take an excellent instructor and record their videos before I get on with it. How many people who are also coordinators for the CS 101 workshop two weeks ago? Okay, so this part the initial little part is going to be the same for you as well as from that course. Okay, so what was done was an experiment saying that suppose let's see how much difference really does the quality of the video or the quality of the way the instructor creates the video matter. Okay, so what happened in this experiment was two video lectures were created. In one case the instructor spoke very well, looked at the camera, did the delivery properly, had perfect diction and all of that. Okay, in the other case the instructor was kind of slouching and you know looking here and mumbling and you know creating the video in a not so professional manner. And what people wanted to see is does the instructor's delivery, how much does the instructor's delivery, how well the instructor is delivering the lecture, how much does it matter towards student learning. So what would you expect? The one who's delivered it very well that person's students are going to learn better. Right, that's what we would expect. It turns out that when they measured the learning using a test they found that even though the expectation was very different. Right, people expected that in the case of the fluent video students would learn a lot and in the case of the disfluent video the students would learn very little actually speaking there was no difference in the amount of learning that happened. Okay, so what does that tell us? It basically tells us that simply improving the fluency of lectures does not necessarily imply better learning. Okay, so as teachers we are always focused on improving our own delivery. We are always focused on saying okay I need to I didn't do a good job of explaining that part I need to improve that part. Isn't it? We all do that. So what the point that this experiment makes is that instead of focusing on our own delivery so much we need to start focusing on what makes the student learn better. So change from instructor-centric way of teaching learning to a student-centric way of teaching learning. So then we ask the question that suppose I have excellent video and I have interaction. Okay, there is a local instructor who is doing the interaction and I am going to do an interactive classroom. Okay, where students are free to ask questions I will ask questions I will interact with the students. Okay, is this good enough? Yes? Okay, so by and large once again we feel that yes this is good enough. Okay, if just the video is not good enough maybe I'll add some interaction with the students to bring them into the classroom make them pay attention. It turns out that this is necessary but it's not sufficient. Why is it not sufficient? It's not sufficient because primary reason is that students don't pay at most attention. Okay, usually we are the ones who are most thrilled with our lectures. Right, we are always thinking that I'm doing a great job. Everybody's listening to me. Even now, every time, even however much we are aware, I really don't know what's going on over there in people's minds. You know somebody's thinking about breakfast, somebody's thinking about how the Gandhi Nagar Me, the bus took a turn and all those things. Right, so it's not entirely, nobody's really paying as much attention to me as I think people are paying. That's the key. Okay, the second reason is students think that they know the topic because they are able to follow the lectures. This is often a major drawback of excellent lecturing.  So the misconceptions that they have or the points which they have not understood, they are confronted with that only much later. Okay, later being in the exam. Okay, and that's why as instructors, we often feel that I did such a great job of teaching but still these fellows are not able to score marks in my exam. Okay, that's where that feeling comes from. Okay, the third point is it's difficult to ensure that all the students in the class participate actively. Okay, so students with high motivation levels will drive the pace. Often you find that in your class you will see that there will be those four students in the first two, three rows who will keep on asking questions, who will keep on saying something or the other. And before we know it, we are responding to those guys and the rest of the class gets left behind. Okay, it happens to all of us. Has it happened to you? Okay. So students with low achievement levels get left behind. And finally, however interactive the instructor may try, the students have a barrier to responding directly to the instructor. Okay, so there is some amount of shyness and there is some amount of diffidence which students have in responding to instructors. So if we have a tactic which tries to force everyone, so there are some instructors who use a tactic saying that they'll point at somebody and say, okay, you answer or you answer. What happens next class? That person bunks. Right. So that's usually what happens that you don't want. So those tactics also often backfire. So what we want is a method where this without four, six students, we are still able to get them to interact. We're still able to get them to engage with the content. Okay. So those techniques are called active learning. Okay, the difference being that instead of passively listening in the classroom, what the instructor is explaining or some small amount of interaction, the students are actively engaged with the content. Okay. So getting students to talk, write, reflect and express their thinking. Okay, many of the times we do this in our classroom. We do it informally. So there are some requirements for a strategy to qualify as an active learning strategy. One is that the instructor has to pre-plan and create these activities. Students go beyond listening, copying notes and so on. And the last two points are that these strategies are explicitly based on theories of learning. Okay, it's not a strategy which is like, okay, I think that will work. I think this is what I should do. It's based on a theory of learning saying, okay, this is the structure of how students motivation works. This is the structure of how memory works. And then the strategy is created so that we can address it appropriately. And many of these strategies are evaluated repeatedly through empirical research. Okay, so this broad area is called active learning strategies. Okay, so before I go on to talk about actual strategies, I need to convince you that it's even worth listening to this guy. Right. So, okay, all this active learning is fine. Is there really a benefit? So there were, there was a very large experiment that was conducted. Okay, so this experiment involved 6500 students across 62 courses, across a variety of institutions. And they had a test which is called the force concept inventory, which is a standardized test for one topic in physics. And what they measured was how much do students score on this test in various instructor's classrooms. Okay, so what you find is that what is being calculated is something called gain. Okay, gain means how much did the student know before versus how much does the student know after. Okay, so everybody knows something about force right from their school days. So how much did they learn, how much did they gain as a result of the classes. Okay, and it turns out that the maximum gain from lecture courses was 0.28, okay, which is somewhere around here. Okay, all these red bars. And all these, most of these lecturers were excellent teachers. Okay, they had terrific command of the subject, excellent delivery, all of that. Still it was found that those students, the gain was only 0.28. Okay, on the other hand, for instructors who are using some kind of active learning strategy, the gain was fairly spread out all the way from 0.2 or 0.23 to 0.7, depending upon how well the instructor was able to use that strategy. Okay, so what this basically means is that even if you are an excellent lecturer, if you incorporate active learning strategies in your classroom, the amount of learning that your students are going to have is going to increase a lot. Okay, that's one thing. The second thing is even if you're not that great a lecturer, okay, which many of us don't feel that I'm that great, I'm average. You know, many of us have that feeling that I'm average, I'm not that great, I'm not that bad either. So especially for such instructors, incorporation of active learning strategies actually manages to get them to perform or get their students to perform comparable to those who are doing excellent lecturing. Okay, so that's the implication of this slide. Okay, so what I'm assuming at this point, I would have spent a little more time on this if all the buses had arrived on time, but since we have lost some time, I'm not going to spend more time on this, but I'll assume that you're convinced that there is some merit in this idea of active learning strategies. So what are the features of such strategies? So one is students engage in problem solving activities during the class time. Okay, so often this problem solving activity is relegated to after the class time. So in the class they come here and sleep and then just before the exam, they go back and study. Right, that's usually what is the policy that we follow. So it's like flip classroom, what you would have heard earlier is also one such strategy which makes students engage in problem solving in the class rather than outside the class. Okay, so student ideas are elicited and addressed, students are asked to figure things out, they're asked to express their reasoning, all of that. Okay, so there's a whole bunch of advantages of active learning strategies. What are these strategies? Okay, there are many of them and they're all well studied activities, think-pair-share, peer instruction, team-pair-solo. So flip classroom, for example, is based on this peer instruction strategy and what I'm going to be talking about today is this one strategy called think-pair-share. Okay, so let's start with just executing one of these activities. Okay, so what you have to do is consider a large class where there is a huge auditorium and there are 450 students and imagine 90-minute lecture in such a classroom. Okay, right now I think I am 10 minutes into this class and already I can see people's eyes closing. Okay, so imagine 90 minutes of that. All right, so now what you have to do is predict the percentage of students who may be showing engaged behavior with the content of the lecture at various instance of time. Okay, so what you want to do is you want to say that, okay, in the beginning students' engagement is somewhere here, then slowly it increases, then it goes down, maybe it increases again, whatever. Okay, so I'll give you two minutes to predict what that graph will look like, okay, each of you.  Okay, don't start talking to anybody yet. Just imagine either your own class or maybe the class of your favorite instructor or anybody and predict over 90 minutes, how is the students' engagement or how much are the students going to pay attention over a 90-minute class? Is the question clear to everybody? I still see some people who are sitting. I need to see pens moving. Draw a graph of engagement or how much students are paying attention versus time as your own lecture progresses. It's for a traditional lecture, yeah, I mean you can imagine your own lecture, it's fine. It doesn't really have to be traditional. You can say interactive lecture, doesn't matter. Done? How many people are done? All right, most people are done. Okay, so let's move on to the next step. So this was the think step. The next step is, along with your neighbor, whoever is sitting on left, right, examine each other's graphs. So you have an interesting graph, you have some other interesting graph. Are they looking the same? And then together come up with a technique which can make the graph look like this. Basically what we are saying is 80% of engagement almost all through the class. It's not like it's increasing. So many of you would have drawn a graph which goes up and then slowly goes down and comes down somewhere here. So you don't want that graph. So what you want to come up with is a strategy by which this stays up. So talk to each other now. So first examine each other's graphs and give your logic as to why you drew the graph that way. All right. I guess most of you would have thought of some ways. So let me do one thing. Let me write down your ideas. Okay. So something like that at a regular interval of some time so that they'll be reactivated. Okay, quiz after every 20 minutes. Yeah, then at the mid of the class I can discuss something out of the subject. So what we'll do is we'll make a list of these strategies and then we'll examine if that will help us to sustain the engagement. Okay, it can bring engagement. Can it sustain? That's the question we'll ask later. Okay, so as and when I'm putting up strategies, if you have a strategy which is different from what is already being put up, then respond. Yeah. Real-time examples. Real-time examples or real-life examples. Okay, asking questions to students. After doing some board work roaming throughout the classroom. Roaming throughout the classroom. So every 15 minutes I'll do some funny things to wake up a sleeping student. Such as what? Some jokes. Okay, jokes. Yeah, real-time jokes and okay. Activity-based learning. Activity-based learning is just a term. So what do you mean by that? Real-life examples are already there. Actually show that activity, ask the students to come up and engage that it will take around 5 to 10 minutes to show actually that example. Okay. And second is peer-share after quiz. What is that? Peer-share. Let us allow the student to discuss on some topic for 5 minutes, 7 minutes then make a quiz for that. Okay. Peer-share after quizzing. Okay. Then anybody else? Somebody from this side. Yeah. Sir by specifying the previous year questions also. Specify. Okay. So specifying previous year's question, do you think it'll bring engagement in the class or they'll think that, okay, I've got last year's questions. I'll just go away. Yeah, go ahead. Share short stories. Huh? Share short stories. Share stories. Then after every 10 minutes I'll say loudly, break. Then every story is fine, interesting, and released from my talk and I will not definitely give break for 5 minutes, but after 2 minutes I will again start my cut. But when the word break is heard, they are okay. Everybody's waiting for that word break. Good one. Yeah. Learning by demonstration. What does that mean? Suppose we can demo the concepts, those we have explained just up inside the classroom itself. Okay. Demo, showing demos of concepts explained. Yeah. Animations kind of. Yeah, demos and animations. Yeah. Yeah. Go ahead. Refreshing YouTube videos. Yeah, demo of concepts explained, animations, videos. Okay. The last two more role play. Okay. How will you do role play and computer networking? Actually you can. So it's not so hard. So in fact, let me tell you. So in fact, there was, there is a paper which, you know, some of our, we ran a course like this for teaching teachers like you to do active learning experiments in their class. One teacher, she actually did a dance of, that's you. Okay. Why don't you tell about your strategy? To share with you all, I have written 40 lectures with 40 different activities I have experimented. Can you tell your name first? Myself Bhavna Ambedkar from Padmashi Doctor D.Y. Patil Institute, Pimpri Pune. I have done for all the subject contents, all 40 lectures with interactive sessions. As you have asked, sir, this I would like to say every 60 minute lecture I have planned with the activity after 10 or 12 minutes, I have planned activity. This book is called as faculty resource guide and which is released by Vipro Mission 10x. Okay. Thank you. That dance activity I did specially for a seven layers of OSI model. Yeah. And she wrote a paper about it. Okay. Role play. Anybody else? Yes, sir. What I do is that I give some problems related to computer network and whoever is the first who answers correct answer gets a chocolate from me. Sir, we'll give the application, industrial application of the concept and ask a problem to solve in 5 to 10 minutes. Industrial application and ask problem to be solved. Okay. Okay. Last. What is state of art? So, how does that bring engagement? You have to say how whatever it is that you do will bring advancement. Talk about described state of art. Okay. So, stop here.  Okay. So, some of them are momentary engagement techniques. For example, telling a joke. People are engaged when you are telling the joke. Once the joke is over, they go back to sleep. Okay. So, some of them can do sustained engagement also. Like for example, quiz after every 20 minutes. But then on the other hand, will they come back for the next class? That's the question you need to ask yourself. Okay. So, many of these things are there. I'm not going to do that today again because of lack of time. What we'll do instead is move on and try to write some of these activities for networking. Okay. So, the third one is to create a combined list of techniques. That's the share phase and discuss the pros and cons of each technique. We have not really done that thoroughly. Let me move on to talking about what is TPS. Okay. What is this think-pair-share? So, what we just did is called think-pair-share. Okay. So, there are three phases. First phase, what did you do? You thought about a problem. You worked individually. Right. The second phase, you worked with a neighbor. And in the third phase, we all talked together and we all shared the answers. Okay. So, that's basically the think-pair-share as the main things. Okay. Why is it useful in large classes? Like blended MOOCs or large remote classrooms and so on. Because the well-known challenges of teaching learning in large classes apply to these blended MOOCs. Okay. I mean, if you're going to talk to a student through a camera who is on that side, you really have no control about whether the student is fiddling around with the mobile or doing something else. So, what's important is we want active learning techniques that engage the entire class. See, the keyword here is entire class. Okay. How many of you drew a graph? When I asked, saying draw a graph, how many of you didn't draw a graph? That may be a smaller number. Right. And most people were engaged. Even if you didn't draw a graph, you're curious. What is, what graph is that guy drawing? And when I say, okay, start talking, everybody wants to talk. Isn't it? So, that's the idea. You're able to engage the entire class, not just the subset of class, which is talking to you, which is responding to you. So, it's a relatively easy way to achieve the benefits of small group learning in a large session. Okay. You also get an idea of how, how much people have learned. No rapid feedback that you can get. Okay. So, quickly for the definition, instructor poses a problem. Okay. In the first phase, the teacher asks a specific question about the topic and students think about what they know and come up with their own individual answer. Okay. Second phase, teacher asks another question which is related to the previous one.  Okay. Everybody can draw that graph because everybody has sat in a class. Everybody has stood in a class. All of that is happened. Right. And then you say, okay, now come up with a strategy which will change the graph so and so. Okay. So, that's the next question that the teacher asks. And finally, you share all the solutions that come up. You discuss pros and cons and so on. So, this is the basic three phases of think-pair-share or TPS as we call it. Okay. Why does it work? Students are actively engaged. Right. All of you are engaged when we said, okay, how will you make that graph? Students learn from each other. You know, reduces the burden on the teacher. Basically, that's the main point. It's a very good strategy for lazy teachers. Okay. Let students learn from each other, reduce your own burden.  Okay. So, and more importantly, students can tackle large, ill-structured problems. Okay. And develop the ability to consider multiple points of use. Many other benefits are there, makes the class interactive. Students realize that even others are struggling. That's again an important point. So, when you find that, okay, you've got the wrong answer and it's okay. The other guy also has got the wrong answer. You feel a little better. You feel that, okay, it's not that bad.  Things like that. Okay. So, all of that is, are the benefits of TPS. So, how do we introduce TPS in such large blended MOOCs and large-scale teacher training programs? First of all, why should you care is that you can have, as coordinators, you can have TPS activities during the synchronous interaction phase. So, you have some control over what's going on in your remote center. And whatever your students learn depends upon how well you execute your TPS. Okay. So, what does a TPS activity look like in networking? All this is fine. Generic stuff that I talked about, engagement and so on. All that is fine. In specific to networking, how does TPS look? So, here's an example. So, this question comes after the initial lecture, right? So, we all start with talking about either the OSI stack or some TCP IP stack. We say, okay, physical layer, network, MAC layer, network layer, transport layer. Okay. So, we describe the stack. So, after that, this is a question that I ask my students. So, I'll give you a few minutes to read it. And then we'll discuss whether this is a good activity, if so, why. So, what's written under think, pair, share is what I get the students to do in each of those phases. Okay. So, is that a good activity? Why? It is easier than listening to the class. Okay. In that subject and in that topic, instead of okay, they will concentrate on the topic. What's going on in class? Okay. Since they came up with some ideas, they'll remember it for a longer time, right?  I might tell you, okay, layering has its advantages, modularity, abstraction, this, that. All those are just words, if I tell you. But if you identify that, look, because of layering, I'm getting this advantage, that is going to stick with you. That's the point. Yeah. They can extend their knowledge. They can extend their knowledge, okay. So, let's come to specifics. So, these are some of the broad advantages which are true for any TPS activity. So, what we're asking is, why is this specific activity, like technical activity? Good. Why is it good to ask them to write one reason for and one reason against layering? So, we'll get a different answer. Okay. We'll get different answers from different students. Yeah. Some amount of self-learning will happen. Okay. So, that again, I'm going to put up, put it in the category of general advantages of TPS, okay. Specific to this question. Again, that's generic. So, let's not talk about generic advantages of TPS. Yes. We get different answers that shows their creativity. I mean, that shows their creative mind, how they think and how they come out of that question. Okay. Creativity is again here. So, what I'm looking for are specific answers. Okay. From this exercise, students can know where we apply the layers, how can we use these layers, where we do not apply particular thing due to the advantages and disadvantages. Right. And know actually what the need of knowing the layers. Okay. So, this is, so, I'm looking for answers of this type. Okay. Which is very specific to what we have put up. So, one example is, by discussing, students know when not to use layers. Typically, we try to say this is always a good idea. There are instances when it's not a good idea. Let them think about it. When not to use layers. Okay. Anybody else? Yeah. Exploration of the domain and then by saying it will grow up for all the students. Okay. So, I'm going to put that also in the generic advantages. Okay. Specifics. Let's get into specifics. Visual realization. Visual what? Realization. Of. So, whatever the things happening, there'll be visual realization of the data, whatever things happening there. Okay. Layers, I don't know. Okay. Visual, let me write it anyway. Okay. Anybody else? They are also made to think about others' ideas. Okay. Think about others' ideas on layering. Okay. I mean, it's like, I might feel that this is good. It's like choosing a political party. Right? I mean, you might have one choice. Somebody else might have another choice. And then you have to have a debate. Basically, the activity encourages debate and debate improves understanding. Sir, by giving one answer against and for the motion, they'll get to know another 10 advantages and disadvantages of the layers of the layering concept. Right? Because I come up with one, 10 is a little far-fetched because 10, I don't know whether we'll be able to, because most of them will be similar. Right? I mean, I'll come up with one advantage and disadvantage. You'll come up with one. There may be a bunch of five or six such answers. Yeah. Last one. Actually, each layer is a different layer level of abstraction, though they'll understand what is the good in having the interaction among the abstraction and what difficulties can it be. And they can apply it in any other strategy also. Let it be object orientation or anything too. Okay. It makes them understand the interaction. Okay. So, I'll stop with that. Okay. They can't talk about discuss, introducing new layers or remove existing ones. Okay. So, that's again, we are getting them to engage deeply with the content. Yeah. Individually, they are able to only solve the some part of the task. And by collectively, as an entire team, all layers, they will be to solve the whole problem of that area. Okay. So, individually, they can only do small amount. Collectively, they can do a lot, which I'll again put it in the generic advantages. Okay. Okay. But specifically, now, what you find is that by doing a TPS activity like this for 10, okay, last, absolute last. The active student will be active and the active student will be deactive even you two inspire or anything like in team of two. Okay. So, the point is, let me address that question. So, the point he's making is active student will be active and non-active student will be not active. Yeah. You know what happens in a classroom? See, for example, if somebody next to you is sleeping, he's going to find it very difficult to sleep when you're talking. You know, that's the problem. So, it does make up non-active students. They may not really want to engage. They may not want to hear layering, but everybody is saying layering, layering, something, something. Okay. This fellow is eventually going to pay attention to say, what are these fellows talking about? Maybe tune for sleeping. Yeah. So, we are not trying. Okay. One thing we must remember, we're not trying for 100% at any point. Okay. If you are able to carry 80% of your class, you're doing great as an instructor. Okay. Because typically, you're carrying 20%. So, when 20% you're going to 80%, don't attempt 100% because that's killer. Okay. So, now, coming back to this, if you look at layering, what we have done is, typically, however good a lecture I might have given, I would have just said a few things. Right? I would have transmitted. That's called the information transmission model. I would have transmitted some information about layering. And the student may have thought that, okay, I understood it. That may have taken 10 minutes. Now, in the same 10 minutes, what you are achieving is they are engaging with the content. They are coming up with ideas. And it has been shown that they would have learned more deeply than through an excellent lecture. Okay. That's the point about carrying out activities in this manner. So, total time of this activity is about 25 minutes. Okay. Actually, I've got it wrong. So, it should not be 10 minutes for the pair phase. Never mind. Okay. So, moving on, let's see about writing an activity ourselves. So, now, assume that you have finished with the network layer and now you're starting to talk about reliable transport and so on. Okay. So, you want to get students to get to the point of what exactly is there in TCP? What are the concepts in TCP that lead to reliable in-sequence delivery? So, what you have to do now is to write what you will ask in the think phase, what you will ask in the pair phase and what you will ask in the share phase. Is the question clear? You want your students to think about what is, how does TCP provide reliable in-sequence delivery? You don't want to tell them the answer, mind you.  So, you have to write what should be done in the think phase, what should be done in the pair phase and what should be done in the share phase. Yeah, somebody had a question. If we have, we are supposed to teach whatever we are having technical knowledge. We are not teaching them literature. We are supposed to uplift them technically. So, in this way, we have lost 25 minutes which were crucially important for us to deliver more and more technical information to them and those things we can provide them in making tough assignments also. Okay. So, the question is, have you lost the 20 minutes that we did on layering? So, just go back to thinking about the layering example. I did not tell you about layering. I made you do this vague activity. What is at the end of it? Did you learn or did you not learn? The chances are that you have learned. So, that is the point. So, I am not saying that do your entire class in this manner. That is wrong. But having one or two such activities in a one hour class not only helps engagement, but will also increase learning. I will show you some data later on as to why it actually works. But the key idea is that the fact that when we think that okay, I have to transmit information. I have to tell them something technical. That is a misconception because they are not listening. Sir, my point of view is that these all type of activity can be done only in the tutorial. If we are doing these type of activity in our normal classes, then in some way we are disturbing the other classes also. And if we are going to take all this type of activity, making joke, making dance, discussing something, this simply means that we are not technically prepared so well. Well, this is a lot of your, you know, you are trading on very nice here. Just so, you know, students are so smart, they can easily understand today what the teacher is coming with, what energy level, and how many minutes he will teach perfectly. If we are making jokes, I said something simple. It means I totally spoiled my lecture. If I simply discuss that, I am not advocating telling jokes of that sort, first of all. Second of all, I am not advocating use these strategies because you are ill-prepared. You have to be more than well-prepared in order to execute such strategies well in your classroom. Otherwise there will be utter chaos. The third thing is about the noise factor. See, there is going to be noise in your class. Your class is going to look different from other classes. There is no doubt. The point is to show to your colleagues how much learning is happening. Get your colleagues also to have noisy classes. That is what we want to get at. Okay. So, let us come back to track. I will take more of these general TPS benefits and disadvantages type of questions at the end. Let us first write to an activity. Okay. So, this is the question. What you want your students to do is to guide them towards discovering how does TCP provide reliable in-sequence delivery. Okay. So, you need to write what is there in the think phase, what is there in the pair phase and what is there in the share phase. And there is no single correct answer over here. So, do not have to wait for that single correct answer to appear. You can do this as groups.  So, you can discuss with your neighbor and just together come up with what you are going to do in the various phases. So, in each phase, you have to write what will you ask the student to do. Okay. Not the answer. For example, you may say in the think phase, you might write a question like how will you ensure that I know whether a packet is lost or not. Something like that. So, that kind of questions is what you want to write down. Why reliability? Why is reliability important? Sure. I'll note it down. Just I'll give you a few minutes to finish writing. Just just hold on. Let's not go into sharing till people are done. Okay. I am ready to wrote down. Who wants to go first? Yeah. If you are starting from scratch, then give some non-technical question which relates to TCP reliability like in sequence reliability. So, for example, in think, you can ask them to write advantages and disadvantages of registered post and simple post.  Okay. Other students and come with the solutions. Okay. Advantages and disadvantages of pair phase. Wait, wait. Let them finish. In a pair phase, they will share advantages and disadvantages of, I mean, with the nearby students. Okay. Yeah. They will come up with what are the pros and cons. And then share, they will share again. All students will share the solutions. Okay. So, how will this achieve the objective of getting them to understand acknowledgement is there in the registered post? Well, in the simple, I mean, we don't have any acknowledgement. Okay. So, that is the point. Okay. Next. Somebody started speaking there. First, we will ask them what is in sequence delivery? In the thinking stage. Okay. Then, in the pairing stage, let them discuss if it is out of sequence. What could be the pros and cons and why this in sequence is required? Okay. And another could be the like, what is reliability in delivering the data? Liability. Okay. Okay. I'll come to discussing each other. Let me write down a few. Yeah. Think how to establish the connection and who will be involved in that. Okay. Connection and determination and who will be involved in that pairing stage. Discuss how actually the data will be transmitted and what will be the intermediate parties they will be involved for actually data transmission or loss. Okay. In the sharing stage, discussing all about the advantages of reliable and unreliable transmission by taking an example of... Okay. First, we have to know what is TCP and to end responsible for end-to-end communication in thinking phases. Then, pair we have to... What is the question? What is it that you will ask them to do? What is reliability? Okay. That's the question you will ask them to answer. Then in pair, what is sequence numbering? Then share about how to use sequence number to achieve reliability. Okay. During the pairing time, we are supposed to give an activity-based question. So, I will ask somebody that you have been given five chocolates with sequence number one to five. Now, you are supposed to deliver it to the last guy through your friends. Write down the protocol for that. Okay. With numbers one to five, to be delivered to last student. Okay. Then that is the think phase or the pair phase. So, what is there in the think phase? What is the think phase in the registered post? Okay. So, think phase, you will get them to think about registered post versus ordinary post. In the pair phase, you will say, okay, I will give you five chocolates and these numbers, how you will do? What will you do in the share phase? The protocol that they will write in the pair phase, that is further to be explained in the context of TCP IP, in the share phase. Okay. Good. Go ahead. Think phase. Think phase. Do you need any acknowledgement for sending a query? Okay. And in the pair phase, what are the possible ways of acknowledgement? Okay. And the share phase, so discuss about whatever we have. TCP. Okay. Compare with TCP. Okay. Last. Sure. In the think phase, I will ask the student to write a cheat message. Write what? Write a cheat message, the strip of message to one of your friends in the class and write down the name of the first forward friend. And in the share, pair phase, I will ask them to find out the route through which the cheat message is forwarded and related to computer networks. And in the share phase, I will ask them to find whether they have got a replay. And if they haven't got a replay, go and check what happened to your cheat. Done. Okay. Last. Sir, I will ask them to first in the think phase, whether TCP is a connection-oriented or connectionless protocol. Okay. They don't know. They don't know the answer to that. They might be. Okay. I mean, I just, they can think what are the connection-oriented and connectionless protocols. Okay. Then in pair phase, they can discuss what TCP is actually doing in that phase. Okay. Whether it is a connectionless or connection-oriented. Okay. And accordingly in the same phase, they can think about the reliability also in the pair phase. Okay. And finally in the share phase, we can share with the older class. Okay. So, let me stop here and just look at these answers. Okay. So, let's start from the beginning. So, when we say advantage, disadvantage of registered post was a simple post. So, one point that you want to observe is that most of you have got it right, in the sense that the thing phase, one key thing is it should be accessible to everybody. Okay. And when you ask a question like, what is the advantage of, disadvantage of registered post, pretty much every student in the class can write an answer to that question, irrespective of whether that student came to the previous class or not. Okay. Otherwise, often we are building on information from the previous class. Right. And there's only one person who is constantly attending all those classes, which is yourself. Right. And you are carrying everything in your mind. You're saying, I taught this in the last class. They should be remembering. 50% of them were not there in your last class. And the other 50% were doing something else. So, that assumption that they should remember what I taught them in the last class is invalid. Okay. So, when we write something like this in the think phase, which is accessible to everybody, person who has come to that class for the first time after a while, also can attempt that question. That is a key thing to keep in mind about that. Okay. Then let's take the next one. See here, for example, the next one is you start with saying, okay, what is in sequence delivery? Maybe they write some answer. And the pair phase is building neatly on what the think phase has done. They're saying that, okay, now what to do if the packet is out of sequence? In sequence delivery means 1, 2, 3, 4, 5, all of them are going to reach at the other end as 1, 2, 3, 4, 5. And then as a pair, that is something again, which every student is able to answer. Then the pair question makes it slightly more challenging. Saying that, okay, suppose packet number three is lost. What will you do? What is the protocol that you will set up to ensure that packet number three is retransmitted? Okay. So, the pair starts building on what they have already answered in the think phase. Okay. Similar. The third one is also similar. No reliability sequence numbering. Registered post. Okay. So, let me also comment upon. Yeah. So, this one which talks about act for courier, why are acts required? What are the possible ways of acknowledgement? That again is a good question because some of them may think of negative acknowledgments to begin with. They may say that, okay, I'll use a negative NAC-based protocol. Okay. Then you can get into the advantages of act versus NAC-based protocols. Okay. Let me talk about this one. Write a cheat to your friend, find the root of the cheat message, and looked at what happened to your cheat. This is a good TPS activity, but not for this problem. Okay. So, it's a good TPS activity for routing. It's not. So, that is again something that you want to keep in mind, saying what is your goal? Your goal is to get them to think about TCP's two, three main ideas. Okay. What are the main ideas that you want them to think about? We want to say, okay, put sequence numbers. We want to say, okay, have acknowledgments. We want to say, have retransmission. These are the three main ideas that you want them to acquire before you dive into the details of how these are done. Okay. So, this particular TPS activity will actually get them off into thinking about routing and what happens if there are different routes and so on. Okay. So, coming back, let's see what was the activity that I had in my class. Okay. So, this was the activity that I had given, saying that TCP is a transport layer protocol that guarantees reliable in-sequence delivery. Suppose you have to design a TCP-like protocol. Okay. So, TPS, think-per-share is an excellent mechanism for tackling design problems, you know. See, there's no single correct answer. TCP happens to be that way because that's the way it has evolved. I mean, it's not mathematical law that TCP should work that way. Okay. So, it's good to get your student to go through that process of inventing a protocol. So, this is what my students did. Okay. So, they write down the features that you will provide in your protocol to include reliable delivery. So, the moment you say reliable delivery, they are going to think of acknowledgments. Okay. The moment you say in-sequence delivery, they are going to say some numbering. Okay. And that is accessible to every student. They don't have to know anything about networking to say those two answers. Okay. Then they say that, okay, discuss your features with your neighbor and come up with one protocol. Show through an example how your protocol will handle a lost packet. That's the pair phase. And in the share phase, you compare your solution with the specific actions of TCP. So, in my class, what happens is a lot of argument happens in the share phase because each of these students has invented a protocol. And because he has invented a protocol, he wants to know why this is not there in TCP, why my idea is not there in TCP. So, they'll not let me progress and they'll keep on saying that, okay, but why is TCP doing that? Why it's not doing this? So, a lot of discussion gets generated. And that actually answers your question that a lot of technical material gets covered because of these questions that come in the share phase. Okay. So, this is one example. And I think I'm almost out of time. I'm at 10.30. So, there are a whole bunch of examples which are included in the slides. Okay. So, here's another example about layering. Somebody had mentioned that we can use layering to use the same concept elsewhere in object oriented and so on. So, this is an example which gets them to think about the concept of layering, where all can you find it? Okay. So, you can go through this slide later on which explicitly says what the student should do, what the instructor should do and all. Then there's another example about Wi-Fi where we talk about why should, why does Wi-Fi use collision avoidance instead of collision detection? Okay. Getting students to discover the idea of why RTSCTS packets are required. Then there is an example on addressing, getting them to understand about subnetting and another example of how headers are attached, how headers are removed and so on. So, what I'm trying to illustrate through these slides, I don't expect you to read all of it now, but I do expect you to read it later on. Okay. But what I'm trying to illustrate is, depending upon your goal, is your goal detailing, is your goal conceptual understanding, is your goal protocol design, depending upon your goal, you can tweak the TPS activity so that that particular goal is met. Okay. So, once again you have, what is this one? Okay. Yeah. This is about setting the retransmission timeout. Right. How do you do the exponential averaging filter in order to get the RTO values? Okay. Okay. So, now let me quickly summarize by saying how much difference does TPS make. So, these are some experiments that we conducted, not in a networking class, but in a programming class, which is the CS 101 class, which is taught to 450 students. Okay. And this actually answers many of the questions about what happens if I don't deliver technical material to the students. So, what we did was, we came up with the protocol. So, there was a bunch of PhD students who were sitting in different areas of the classroom, and they were observing the students periodically. So, in a 10-second interval, they would observe every student three times. Okay. And that was an observation protocol. So, we observed a total of 13 TPS activities across the semester, and we found that 83% of the students on an average are mostly or fully engaged. Okay. By actual observation. We also found that when we asked the survey to the students, that did you benefit from this thing, phase, what was your benefit from the pair phase, and so on. Again, their self-perception of engagement matched with our measurements. Okay. The second thing that we did was that I mean, this was the same doubt in our minds, you know, that am I wasting my lecture time, precious lecture time, which I should be telling them something. Okay. So, that is actually the misconception. The precious lecture time is for discussion. What they should do is, watch the video outside. The video is already there. You watch it outside. Come to class and discuss. That's where the learning happens. Okay. What we were trying to see is how much learning happens. So, we had a controlled experiment. So, there was one group. I had two sections. So, in one section, it so happened that I didn't do the TPS. And by the time it was time for the lecture, for the next section, the idea for the TPS activity had struck me. So, naturally, it turned out to be a controlled design. And it turns out that the experimental group which learns the concept via a TPS activity. Okay. Even though all these drawbacks, like you mentioned, that it might appear that the TPS is, no instructor is ill-prepared or no discussion is going all over the place. Even though all those things appear to be so, the group which learned via the TPS activity actually performed significantly better with a moderate to high effect size than the control group. Okay. And the student's self-perception of learning is also high. And yeah, I mean, these are the papers in which these results are appeared. Both of them are fairly top-level conferences in computing education. So, basically, that's our evidence for why the technique works. Okay. So, let me summarize. So, there is a TPS activity constructor sheet. So, if you are interested, if you have got some buy-in into the idea, there is a sheet which you can download, which I have not asked him to print and bring, but you can simply download and use it, which will have guidelines and steps whereby you can create your own activity. So, there are three points to keep in mind. Can you guess what these three points are? Point number one. Think. Huh? Think, share, there are three phases. Okay. That's true. As a designer of a TPS activity, what's point number one that I should keep in mind? How to make them think. How to make them think, but how to construct the activity? Time constraint. He should be able to attempt. That's point number one. Okay. First is, okay, I have not written that here, but the think phase should be attemptable by everybody, okay? So, what we are saying is, ensure that there is a clear deliverable for each phase. If you leave the phase fuzzy, you know, think about something which has no deliverable, nothing is going to happen in your class. Then actually what you're saying is true. That will happen. That some discussion happens, they start talking about IPL, all other things will start happening, except the technical discussion, okay? So, there has to be a clear deliverable for each phase and the think phase has to be kept accessible to everybody. The second idea is that the phases have to be logically connected. They should use the output of one phase in the next phase. So, the pair phase is to build on the think phase. So, if you take the example that we did in the beginning, first draw the engagement graph. The second one was draw the graph or what will you do to get a graph like this, okay? So, they have to be connected because the output of the first phase should be used in the next phase. And the third one is that you have to ensure that there is sufficient time for each phase, okay? So, often what happens is when we are doing this for the first time, it's new to you, it's new to the students, okay? So, students are just sitting there looking at you because something new that you're doing. And you're standing here looking at students, wondering why they're not writing. And after some time you panic, you start lecturing, okay? That's quite often that happens. So, you have to be managing that a little bit. So, if you give very little time and if you start telling much before that, nothing much is going to happen. On the other hand, if you take too long, you know, you say, okay, do a TPS activity, my chai pee kya atam, okay? Then again, they are going to get bored. I know they are going to distract from what you're doing. So, the idea is you should move on when 80% of the class has finished that particular activity. Okay, so now I'll take open questions back to, yeah? A course will have let's say 50s to 60 concepts to cover if you are kind of segregating. And from the looks of it, each activity, especially if you're talking about protocol design, kind of a thing, is more or less like some of the things I've seen. 20 minutes. I would say, especially if you're dealing with a larger, if it's a UG class here with 100 students, whatever, even if you break it into 30, 40 student tutorial sessions, I think that phase itself will easily take 30 minutes. Okay. 20 to 30 minutes, let's say. So, it looks like you could at most test maybe some 10 concepts or other cover material related to 10 concepts, which is better than actually doing nothing. But when there were 60 concepts, you're just making them kind of better. Okay, so good chat. So, if there's anything else you could do for the other... Yeah, so the point is that TPS is not the only strategy. Okay, so for some of the concepts, TPS is a good strategy where you want this discussion to happen. Okay, so the other peer instruction strategy, for example, where there is a single correct answer, you could use the peer instruction strategy over there. And the point is you can pick and choose between these activities. If there are 40 concepts, you say, okay, these 10 concepts, I want everybody to be able to have a good grip of. Only those 10 I'm going to do using TPS. The others, I might simply just go ahead and do an open group activity or do something without doing an extremely formal TPS. You could go ahead and do. Okay, the one thing that I have found is that even though it takes time, it covers technical material at a level which like somebody mentioned this. Because the students are coming up with their ideas, they have a great deal of buy-in. So in one class, let me give you an example. So in one class, it was about queuing, WFQ and all of that I had to do. So it was a one and a half an hour class. I thought I'd prepared for a two hour class. And because I had done it using the TPS mode, the class got done in one hour. And there were like complex ideas which students were finding out instead of my having to tell them. So that is a plus point which actually outweighs some of these how much time does it take.  If you allow a 30 minute or a 20 minute discussion to become a 40 minute discussion, you have lost 20 minutes of your class. So you have to be on your toes to say when to bring it back. Can TPS be applied for all the subjects? Can TPS be applied for all the subjects that I don't know? It can be applied for a large number of engineering and CS type of subjects. More than that, what type of questions is it amenable to? It's amenable to questions where there is this notion of multiple correct answers. So for example, if you want to teach students sorting algorithms, the multiple sorting algorithms are there. One way of teaching sorting algorithms is to go one by one. Say that this is insertion sort, this is this sort, this is that sort so on and so forth and bore them to death. The other way of doing it is give them a problem, saying that you need to sort these things. Come up with your own mechanism of sorting. Each of them will come up with one of them.  You have to say, what you did is actually called insertion sort. What you did is actually called selection sort and so on. So that way they can get exposure. So when there are multiple correct answers, it's a good way of... Hello, sir. Yeah, good. Totally, I am now confused which technique I have to follow because previously we have following CLM method, creative learning methodology. I thought that that was the good teaching methodology. Now, previous class after attending this workshop, madam thought about the flipping class. That was also good and today you are teaching about a TPS. This is also good and I don't know which technique has to follow. Okay, so this is a good question actually. See, that's the whole point. There are many techniques. Okay, so if you say that, okay, I went to a buffet. There were many things I got confused about what to eat. Okay, it's at that level. So there are many techniques. You have to now choose what works for that problem. So like I just answered, flip classroom is good. When you want students to see the content offline and engage in the classroom, okay, often it's combined with peer instruction, where you have a set of multiple choice questions on which students vote, then they discuss and then they vote again. Okay, so that is the peer instruction method is more suitable when you want them to know the correct answer. Okay, so suppose you want to make, for example, suppose you're doing some bandwidth calculation. Okay, so you put the problem, you say, okay, what will be the answer? You give four choices. Let students vote and then have them discuss why you thought this is the answer, why I thought that's the answer. And then let them vote again. So when there are single correct answers, peer instruction is the technique to use. When you want them to learn how to design something, TPS is the technique to use. The third technique, I don't know what exactly it is meant by creative whatever you said in the beginning. Okay, I don't know the details of that, so I can't answer for that, yeah. Please don't mind, sir. You are getting students and we are getting customers and our shopkeeper is always keeping watch on us that what kind of activities you are doing in class. So what is your suggestion for this? Okay, so my suggestion for that is if you get your customers to buy your product, your shopkeeper will be happy. Okay, so if or you also get your peers, other teachers also do that. One way of getting your shopkeeper to agree that what you are doing is sound is to get your customers to talk to them. I have your students talk to your principal and let your students give direct feedback to your principal about whether they are learning in your class or not. And then you will find that your principal will leave you alone. Okay. Hmm. Tell them in case of PD students because they are found to be like an image of having we are mature and we are come to learn new things like that.  So what I found is flipping the classrooms will be better for PD students. So what is your- Perhaps see the idea is that you should use a technique that you feel comfortable with. Okay. Go beyond lecturing that's all I'm saying. Okay. Use a technique that you are comfortable with. So TPS also even in a PG class or when you take this class, this is bigger than a PG class. Okay. There are bigger egos involved here, but still people did their things. Okay. Still everybody executed. So it depends upon how you execute. Right. So and initial there will be some initial hesitation. People say what is this? She is making me do this, write something on the paper and so on and so forth. But after one or two classes, you'll find that they automatically do that. So in my class, after the first two or three classes, I don't have to say what they should do in the think phase. The moment I say think, all notebooks come out, they start writing. Okay. All right. Thank you.