They don't all have the same drive. They don't all have the same buy in when they walk through the door. They didn't all sign up for the course for the same reasons. But, I've been treating them that way for a long time (or as long as I've been the theatre teacher at my school).
It's funny that this has become a problem. In my English classes I've always been the one who has heralded the idea that we need to let students customize their learning. We need to let them take the lead and show us what they can do and then figure out how to do what they can't...yet.
Theatre classes have been different. I've expected everyone walking through the door to turn it into a career. But, I've been blinded by the idea that not everyone who signs up for theatre really wants theatre. Sometimes, they just had nowhere else to go. Just another reality paradigm shift that I've had to make in my journey to being a better teacher.
The current issue is that we are working on two projects right now. One is a 3 dimensional set design model, built to quarter inch scale. The other is the production of the school's musical. We are doing the School Version of Grease - I am also a middle school teacher - it's an interesting balance. At first I believed that every student in the class should be engaged in both projects. Everyone needs a crew job, everyone needs to be putting together an amazing set design model. But, it just isn't working out that way.
I'm glad that I realized this early enough and now I'm having the majority of the class focus on their set models. It's something where they do the work and they can see it come together right in front of them, for their benefit alone. Other students will be working on that as well as doing production jobs for Grease. Instead of being frustrated with the disinterest of quite a few students, I'm going to allow them to opt out of something that they really have no reason to care about - especially if they are not theatre people.
Sometimes you just have to accept that your students don't love the work like you do and some never will.