After reading this thread, I guess all I can say is that I am all the more grateful that our teachers, parents, and mentors trust the judgement of our students.
Our rule of thumb is "Whatever you do, don't annoy [head teacher]"
For students that may be all thumbs, the alternate rule is "Whatever you do, don't annoy [head teacher]"
This annoyance policy is quite effective, since no one quite knows what will cause annoyance. As far as consequences go, well... let's just say that we never make the same mistake twice - though we may become more creative in our endeavors
With the school year rapidly drawing to a close, I would not be surprised to see students whip out their textbooks and term papers - especially on long hauls via road. Since we have many students on our team enrolled in AP classes (mostly Calculus AB and BC), we often study and work on practice tests together. From my experience, there is awfully little mischief that can be caused in such severely limited space.