Digging up sprinklers sounds like more than just a little bit of juvenile hi-jinx, - it rises to the level of vandalism. You could either give the mom one last warning and say that if his actions continue, you'll call the police. Maybe that would be a wake-up call. Or, if the situation has already gone beyond talking to her, call the police. Maybe having the police just show up and talk to mom is what's needed. But, remember that with kids with ADHD, actions must be punished (or rewarded for good deeds) soon after the incident. So if you see a similar incident, you need to take action quickly. I'm not excusing the actions due to ADHD, but since it might be a factor, you need immediate action.And most importantly, make sure that you act in a rational, adult-like manner or you'll make things worse in the neighborhood.

__________________
Yahoo!