Forcing his child to a hobby: meaningful educational measure?

My child is 12 years old and refused to “go to school” last year. What would have helped him at this time would have been an active member of an association (develop social competence) or to have a hobby in which he has the opportunity to get well in something that has nothing to do with school (develop self -confidence). He tried various things in the elementary school period, but after a season we repeatedly deregistered him because he was only whining and apparently unhappy with the selected hobby.