Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Accuracy vs. Precision

Measure the length of the notepad and desk in millimeters and centimeters and their mass in kilograms and grams. Notice how the precision and accuracy differ for each measuring device.

Area Model for Multiplication

Area models offer a visual representation of mathematical operations. Here you will use area models to multiply and reduce fractions.

The Area Model

Use area models to find either the greatest common factor or the least common multiple of two numbers.

Arm Span and Height Measurements

Measure your arm span and height. See how your measurements compare to others when your data is added to a data table and corresponding scatter plot.

Balance Scale Activity

Use your intuition about balance to keep a scale balanced.

Balancing Excesses and Deficits

Create a line plot [with dots] to represent stacks of coins. Then rearrange the dots to form different line plots and watch what happens to the mean.

Building From Directions

Use blocks to build a design from a written description. Try various descriptions to achieve the correct design. View non-Flash version.

Building the Number Line

Classify the different types of numbers we use, and learn how numbers and operations relate to one another. Start with counting numbers and then add integers, rationals, algebraic, and, finally, real numbers to the line.

Chairs, Stools, and Tennis Balls

Find out how many different combinations of four-legged chairs and three-legged stools you can have after covering each leg with one of 30 tennis balls to silence the chairs whenever they're moved.

Comparing Representations

Statistical analysis allows us to organize data in different ways to draw out potential patterns in the variation. Review and compare data represented in a bar graph and accompanying tables depicting relative and cumulative frequency.

Comparing Slopes

Control the slope of lines passing through the origin (0, 0). Keep track of what changes when the slope becomes positive or negative, and when slope is larger or smaller than 1.

Constant Area

Do figures with the same area have the same perimeter? Arrange and rearrange 12 square tiles on a grid, and then measure the perimeter of each shape you create.

Constructing Quadrilaterals

Use a "linkage strip" to to build quadrilaterals with different sets of lengths. Once you build a quadrilateral, see if you can deform it into a different quadrilateral with the same side lengths.

Constructing Triangles

Use a "linkage strip" to build triangles with different side lengths. When you build a triangle, see if you can deform it into a different triangle while keeping the side lengths the same.

Counting Raisins

Count the number of raisins in seventeen half-ounce boxes of raisins. Then come up with a solution to determine how many raisins are in Brand X's or Brand Y's box of raisins.

Counting Stairs

Build staircases out of square blocks. Look for patterns and come up with a rule or formula to predict the number of blocks in any staircase.

Creating a Line Plot

Watch as a physical stack of coins is added as a series of dots to a line plot.

Cylinders, Cones, and Spheres

Is there a relationship between the volume of a sphere and the volume of a cylinder of equal diameter and height? What about the volume of the sphere and the cone?

Dealing with Data


Determining Rotation Symmetry


Grade Levels



Required Software