So if you find a facility that is willing to decorate for you, it will be very helpful. But if you are having your dance at a facility that doesn't help, the students are usually very capable of doing the work themselves. The DJ can make or break a Prom. You need to book a DJ about six months in advance. Let the student committee do the legwork and get the DJ pool down to three or four before you start doing your checking.
References are absolutely essential for a DJ that works a Prom.
Some DJ's may not have the right music for your group, some might just display a lousy attitude, or some may not have enough equipment to play such a large room. Anyway, he has the potential for ruining your dance, so be very choosy. If you get a favorable recommendation, you will then want to ask yourself some questions. The students need to help you make these decisions, and what you decide will make a huge difference in the price. Make a careful, informed decision.