Here is a description of the contest and contest rules from abc.com:
You've heard Katy Perry "Roar." Now Katy Perry and "Good Morning America" want to hear your school roar. Send us a two minute video of you and others at your school performing your own rendition of "Roar" for a chance to win "Good Morning America"'s "Roar With Katy Perry" contest. The qualified school of one lucky student representative entrant will win a live concert by the chart-topping artist to be held at the school on or about October 25, 2013. The concert will also be broadcast on "Good Morning America."
It was filmed by Lucien Arsenault, Malcolm Watts, Scott Sweitzer and Devin Bernard. It was edited by Scott Sweitzer.
Best of luck to them in the contest!