If this is Christopher, I'd say he looks pretty good, considering Christopher was born in 1997 and will be 12 this year. Pretty big for a 12 year old. Arnold's other son, Patrick is 15 or 16. Either way, I don't think its fair to judge the physiques of adolescents, sons of Olympians or not.
Katherine is 20, Christina is 18. checking out colleges was probably for Christina