The ending to this chapter could use some work, but it's pretty believable, and it's easy for me to picture the places and situations. The only thing that's not too clear is the two goons appearances. Come to think of it, I don't know what Roger and Mark looked like in HS either, though I imagine Mark was a little shorter and scrawnier then.
You know, most of your "high school-era chapters are only loosely connected to Rent. With only a little work, you could make them into an original. The only things you'd have to flesh out is why Roger and Mark were friends.