Some 250 junior high and high school students are testing their minds and mechanical ability today at the University of Northern Iowa in Cedar Falls. They’re participating in a regional competition of the Physics Olympics. U-N-I physics professor Larry Escalada oversees the competition that includes several events. He says the students put together a device for each of the events, and the device has to do certain things. The devices include a mousetrap car, a self-propelled catapult, a water heater and a soda straw arm. Escalada says each of the devices must pass a test of its ability to function.For example, with the soda straw arm, they’re giving a certain number of soda straws and pins to build the arm. The arm has to support a given mass. Escalada says the goal is to get students thinking and using the physic skills. He says he’s impressed to see what they come up with. He says the ingenuity and creativity they show in putting together the devices is “pretty neat.” The teams are from northeast Iowa and the winners advance to the state competition.