Taking weights as an elective...I really need to get in shape.

I'm seventeen and I really need to get in shape. I don't have time to go to the gym after school so I figured Id take weights because It'll be required for a grade So Id be forced to work out, Yeah! well, my teacher, it turns out, doesn't care if you work out or you don't. And I'm the only girl in that class. I need some help on what to do! background: I'm in musical theatre so I need to be fit in order to get roles. I did cheer for two years and softball for one and I ride horses competatively. (I think that's spelled wrong but whatever) I do, however, have a stress fracture in my right foot and have loose ligaments for my ribcage, so my ribheads pop out of place frequently. Also, my school is poor so we have NO machines. we have dumbells, bench press areas, and stuff for deadlifts. I go to class for 50 min. 3 days a week and on the last day we go for 90 min. Please help me figure out a good routine! Also, kind of nasty but I sweat. A lot. and I don't have time to shower after and every other week it is not my last class of the day. So, yeah. Help please
Updates
+1 y
Didn't mention this but we are only allowed on the track if our teacher is with us
Taking weights as an elective...I really need to get in shape.
Post Opinion