St Francis 6th graders James Clark, Chase Breemersch and Jacob Rydberg react to a simulated fission using mice traps and ping pong balls during the Nuclear Science Merit Badge Camp at the Cedar Rapids Science Center on Saturday, February 15, 2014. Duane Arnold Energy Center employees volunteered their time to teach local boy scouts about nuclear energy with demonstrations of nuclear half-life and use of radiation monitoring equipment. (Justin Torner/Freelance for the Gazette)