All of the directories under home, except for his own, should be off-limits anyway with privileges of 0750 (drwxr-x---). Most distributions have reasonable file restrictions these days, are there particular areas that you've set up that you don't want users to access?
If so, make sure they're not owned by those users, the group id isn't a group that those users are in and that the 'other' permissions are set to 0. If that last bit doesn't make sense, have a look at
http://www.linuxquestions.org/linux/..._in_Unix_Linux.