A couple of my friends work in school IT departments, and I've always argued with them the pointlessness of trying to filter the internet usage in schools.
- It doesn't prevent the dangerous stuff like kids being groomed by weirdos on the internet
- It's not perfect in terms of banned websites or URLs. False positives occur and how are you supposed to deal with kids aged from 11 through to 18 and all of their learning requirements/subjects, including biology?
- Kids run or install proxies which route through the filtering proxies and they get on MSN and other sites they want to get to anyway. Only the "good guys" lose out
- When they get home they can do whatever the hell they want anyway. If you've been on the internet, you cannot unsee some websites and images!
All it does is give the teachers and parents (who don't know any better) a false sense of security. They get to accuse the kid of hacking or breaching yet more rules and regulations by viewing "banned" websites. The school teachers are absolved from any responsibility and can show that they at least made an effort to stop little Jonny from browing sites he shouldn't.
The only possible solution for kids to be allowed on the internet, is for them to have 100% supervision. Their parents should keep an eye on them and educate them on why supervision is required. The teachers should educate them on the dangers. A portion of their curriculum each year should be whats going on on-line and why they should pay attention.
Then when they are old enough or responsible enough - the kids should be told by their parents that they've reached a responsible age, and now it's up to them to look after themselves and not be manipulated, conned or ripped off. Coming of age and maturity.
There is no other alternative. Letting youths onto the 'net I can only compare to letting them out into cities at night unsupervised. They are exposed to danger which could ultimately become a physical threat to them.