If a student is flying I think it's the responsiblity of the school and his/her instructor. I can't imagine a student will do these things on purpose and he/she should be briefed (like every other training flight) in advance. Since you're dealing with low time pilots, there will always be some extra risks involved .
Rental is another isue. I assume that the flight school first checks a pilot out if he/she is allowed to fly with their equipment (at my flight school this was common)?
DJG