Like someone else said, probably not. Lots of kids/parents use it for school only. Though to take him off for the few days he's out of school while hiking is DUMB (I wonder how long it takes to get back to therapeutic level of ritalin?).

If I recall, some of the side effects aren't that welcome, so over summer the kids just stop taking it. Remember, most kids with ADHD are fidgety and interrupt others, in addition to having trouble with school. So, taking the drug during school helps the whole class, not just that person.