Comment If you go Nazi, you will be pwned (Score 1) 1117
Believe me. If you make the locks too obnoxious, somebody will make you look stupid.
Unless you have a very well-versed and well-paid IT-staff, the computer-literate students in any given high school class outnumber you in available man hours by a factor of about 10.
If you mess up, they'll make sure all the turned-on clients in your school display a rotating technicolor Goatse on a set date and time (been there, done that). Treat them like the kids they are, not like mind-criminals.