The White House held its fourth annual Science Fair today. Hosted by President Obama himself, the Fair featured experiments from students across America who participated in science, technology, engineering and math (STEM) competitions. This year's Fair was especially focused on young women who did well in STEM.

While Obama is used to greeting major athletes win competitions, he wanted to give the young scientists a similar welcome: "As a society, we have to celebrate outstanding work by young people in science at least as much as we do Super Bowl winners because super-star biologists and engineers and rocket scientists and robot builders, they don't always get the attention that they deserve, but they're what's going to transform our society," he said.

Among the competitors were Deidre Carrillo, 18, who built an electric vehicle; Peyton Robertson, 12, who created "sandless" sandbags to better protect flood zones; and a group of second graders from Edmond, Oklahoma who created an alarm that would sound when a car became too hot for people and animals to be inside. You can check out all the participants here

President Barack Obama talks with Peyton Robertson, 12, of Ft. Lauderdale, Fla., about how his sandless sandbags work. AP Photo/Susan Walsh

Obama also used the occasion to announce a $35 million Education Department competition which will train the best math and science teachers. He aims to get more women on this workforce, noting that men outnumber women in the field. (Less than one in five women who earn bachelor's degrees study engineering or computer science.) "Half our team we're not even putting on the field," said Obama, "We've got to change those numbers."

 Obama talks with Elana Simon, 18, of New York City, about her cancer research project. AP/Susan Walsh