couldn't you set up a proxy (?) server that would be the interface between the wire and the kids PC? Maybe a separate Linux box with a big hard drive. Lock it down so the kids can't bypass it. Have it log everything that comes in over the wire.

It wouldn't keep the kids from going where they shouldn't, but at least the parents would know where they've been (from that PC at least).

If the parents don't want them rummaging around the Net, then the various "net nanny"-type things are probably the best bet, but they have a reputation for not working well (not blocking all adult sites, and blocking legitimate sites).

I guess it comes down to what the parents want done. If they want blocking, AFAIK you need software or AOL (I think they have arrangements with some DSL providers). If they want to know where the kids have been, then they need a way to keep track of where they've been.

I hope this helps a tiny bit.

Cheers,
Scott.