Welcome to DB dad!
There's a lot of info about creatine here.
BUT.. here's a pretty good comprehensive article on what it is, dosage and such..
All About Creatine He's taking 6g per scoop, 4 scoops per day.. that is called the loading phase. Which typically lasts 5 days. Since he's doing it for a month.. he's taking 24g a day? That is around 6x more then I do and most others.
5-10g a day is standard. Much more and it's not utilized anyway and you may experience such side effects like stomach discomfort.
I would tell him to quit taking that much per day. 5-10g a day. Maybe some before.. or after.. or all before or after.. but do not continue the loading phase. It was only meant to get the body up to required levels not be on a constant loading phase. I'm sure the directions also state such.
There's also a very nice comprehensive list of creatine subjects from About.com
About.com's Guide to Creatine Overall I'd say Creatine and teens is fine.. but in lower doses then adults. According to the math, he's taking more then 99% of any adults I've ever seen on any bodybuilding board. At tops, people might do 20g a day, but that is usually just a waste of money when 5-10g does the job just fine.
If you need a little more specific help, just holler and I'll do a little more in-depth research for you.