Given your situation, with a number of schools expressing interest, you may want to take your time and investigate each opportunity fully. Once you've gained enough insights into where he may want to go and why, then he can make a fully informed decision.
Too often, I see young men commit real early, who would have had additional opportunities of which some may have been better, but they jumped at the first school who showed them some love and end up leaving other good options unconsidered.
There is nothing wrong with saying 'Thank you for your interest. I'm gratified that you think I can contribute to your program, but this is so early for me that I feel I need to figure out where the best fit is, and then make my decision'. As long as your son is diplomatic in how he explains himself, nearly all schools are understanding. If they love him today, chances are they still will tomorrow. One of the 2012 players in my summer program is going through this right now, and is handling it very well. He's simply telling the coaches that he didn't expect interest this early, since he hasn't even played his junior year of high school ball, and that it has caught him a little unprepared and that he feels he needs to visit the campuses he's interested in to figure out where he fits best and then will be able to give them an answer. Most everyone he's explained that to has been understanding and accepting of that explanation. He and his parents are visiting campuses regularly now and hope to make a decision right after the end of his junior year of high school.