Four guys vs. four girls (maybe one each class). Use TV tunes CD’s (they are expensive but have many uses and are worth the investment). One from each team steps up with a big pot on their head and a big spoon. When they think they know the answer they beat on their heads for a bell. Correct answer and each member of the other team puts in a marshmallow. Wrong answer and your team puts one in plus another one if other team gets right. If it is going too slow, you may want to have bonus rounds for double penalties with anyone on the team being able to sound in and guess (need 8 spoons then). Have rags for them to spit out marshmallows as they drop out. Also, may be done with kazoo or current music. Obviously a great sell is a game show host.
DR Guy/girl teams again. One guy vs one girl at a time. Each has squirt gun and squirts other while song is playing until they get it right.