I have setup security at some schools and I can tell you the following:
* Security is generally setup very strict to ensure that it can not be breached from internally
* There are loads and loads of Audit trails, so even if you manage to get through - you will get caught!
- I recomend rather to speak to the teacher and arrange for special access during specific times of the day
- I am convinced that if you approach it correctly, they will give you the access you desire
** Under certain circumstances, breaching the security at your school is a felony - be warned.