What kind of parent?

I've been having some trouble with behavior in my middle school choirs - especially boys and especially 6th grade. Today I had two students who are friends in the period following chorus. One boy had been singing wonderfully - doing his solfege signs and using his falsetto voice. The other was screwing around and not following directions at all. In the following class they were sitting next to each other and I commented that the one student was singing beautifully and doing the hand signs. I then asked the other student what was going on. He was friends with a guy who liked chorus and everyone around him was doing their work. He responded that his mom made him join chorus.

That's my round about way of asking - Which kind of parent do we want to be? To have on our side? I look at the situation. If the student doesn't want to be in something he/she probably won't give it their all if being forced to. These students seem to create an atmosphere that doesn't facilitate good learning for anyone. Who is truly suffering here? Students that are forced to do an activity actually seem to lose respect for it. I struck up a deal with the student - give me what you can without disrupting and I will make it as fun as possible. I feel this will improve the messing around and will keep the others focused. More to follow halfway through the semester.