Keep all paperwork regarding the purchase of the MBP at your home. Should anything happen to it (theft, for instance), it is covered under your homeowner's policy as long as he is a college student. This actually applies to all of his electronics and possessions.
Advise him to back up all of his data and documents regularly.
And, never let anyone else use his equipment. People will beg and plead to borrow his machine, but no one will ever treat it with as much care as he does. They'll spill stuff on it, break it, and visit all sorts of rogue sites (read my lips: porn).
Trust me. I'm on my third college student now, and I've seen it all.
Edit: One last thing, and this isn't really security, but advice from my son who is entering his sophomore year in college: Do not under any circumstances attempt to download any pirated songs, movies or software, especially if you're connecting over the college network. College networks are heavily monitored. My son knows of at least two students in his dorm alone that received warrants for illegal downloads.