As you sit down to as you sit down to dinner, how much of your plate will good to waste? in tonight's climate challenge, anne thompson visits with students who are going above and beyond to make a change that experts say can have a serious impact on the planet. >> reporter: lunchtime at hilliard horizon elementary, and the cafeteria is a classroom. students sorting their waste better than adults ever do. when you get older, are you going teach your kids how to do this? >> yes. >> reporter: what's motiving the kids? >> i think trying to do the right thing for the planet, for the environment. ...