i think it'd be good to give this guy a warning. but, because i've been in the same boat, I know it won't work. some of us young people are totally addicted to the internet.
so, best thing to do, is to monitor how well he does his work, regardless of him using the internet. if he uses it constantly, but still manage to finish his work, then that shouldn't be a problem. if he doesn't finish his work, that should be cause for concern.
so, best thing to do, is to monitor how well he does his work, regardless of him using the internet. if he uses it constantly, but still manage to finish his work, then that shouldn't be a problem. if he doesn't finish his work, that should be cause for concern.