How to photograph a graduating class on a sunny day?

I recently volunteered to be the photographer for a grade eight graduating class. The pose will be generic and I won't be allowed any other equipment aside a tripod and an SLR. They want this to be done as quickly as possible. It is VERY sunny out there. I realize that this will cause a problem with shadows. Any ideas for settings I could use? Also, this will not be taken with a wide angle lens due to distortion.