Also, to have a blast recognizing some little-known or embarrassing accomplishments of particular seniors. This idea is sort of an alternative to the more formal activities. The awards given at the event will be different from those at most others. You will also want to award important stuff like best male and female role models and persons who best lived out their faith.
Awards can be actual trophies or plaques or papers.
The Needs Location - preferably a nice room on campus or special room in a banquet hall or restaurant. You could even do it in someone's home or yard if it is big enough. Try to get the room donated. Ask around for a parent's committee to prepare all the food for the event. Make it nice.