The issue is a moral one. Privacy and all ethical considerations are there.
IMO: He should contact the school with the info that he has and let them decide what they want to do.
on a lighter note: As this information has surfaced, so we as parents should do something about the issue, right.
So every parent reading this should, if he agrees with me, that family and religion is important; and that our children should be protected, contact the local school in their area and ask them to make sure, that our children are protected, when using the school computer lab.
And parents at home can also use
OpenDNS | Providing A Safer And Faster Internet to secure their children.