I would play Strauss waltzes loudly at my boat and it would keep the kids at bay.
Years ago when I went to a Mall and there were kids just hanging around I told my wife a good dose of the Blue Danube would clear the area in 5 minutes.
If you have a hard core situation and can't drive them all off then switch to Lawrence Welk. In that case I probably would leave the area myself. Lovely Lovely Lovely. -tom