This has happen twice to us with this same guy. My partner and I are playing a set of tennis. We are about 4.5 to 5.0. We know that the court is reserved for 9'oclock. This guys who is giving lessons to kids at 9 shows up about 10 to 15 early and sends the kids onto the courts while we are playing. The kids are now messing around on the side of the court. This bothers me because, I feel really uncomfortable playing and serving with the kids in possible danger. What should i do with this guy. Talk to him and all he says is "You're not going to hit them." "Mind your own business." He sends the kids in 10 mins early and puts them in possible injury. All he does is say: " I have the courts at 9am for a lesson." And it's ten to nine. Does he think he owns these courts? Sorry just venting.