Good thing your not from around here. Our local court systems take a family approach to delinquent kids. Mom and Dad get to have jail time right along with junior if he becomes to much of a problem.
It doesn't happen as much now but still it does occasionally happen!
It seemed to pretty much proved that parents still have the ability to control their kids if they have a real good reason placed on them.
Plus it definitely helps set a good overall example for the rest of the community too. It gives the parents of the other trouble makers an incentive to take a more active effort in making sure junior keeps his poop in a group!
mhmmm I wish my parents would do time with him...not that lucky though, and I'm not in school. School my things would of been safe, I was considered a columbine risk. :/
Look up some info on CCD modules, they're what digital cameras use. You can get ones that are designed as replacement parts for cellphones. Be careful handling them though, they're usually extremely sensitive to static shock.
You might be able to interface one with a PIC, though I suspect an FPGA would do a better job.