I am curious, if a neighbor'S child was throwing baseballs into your yard, nothing was damaged and a further incident did not take place, would you call police?
Baseballs break windows too. . .
We actually had an issue with baseballs hitting the house once. The new-ish neighbors across the street would get up a game in the street (small, quiet street, lots of them played in the road there; I always felt off about it, but it was how it was). After they broke out one of their own windows the parents told them no more baseballs in their yard so they turned everything 180 and batted into our yard.
I absolutely went out and told those kids (12-14 at the time, much older than the kid in the OP) that this was unacceptable and they could not now risk damaging our windows and that our DD (only one at the time) slept in the room with a window on the street and could also be really hurt if they put a ball through our window. I was firm but not yelling and took the time to explain why they couldn't do what they were doing, even though it ought to have been obvious to them based on the already broken windows (yes plural) in their own home, but I still did.
I think I had to say it 2 or 3 times before it stopped, and might have even informed them that any balls that touched my property would not be returned after that last time, but calling the police for kids playing stupidly when no one was in serious danger and nothing was damaged truly never crossed my mind. People were being stupid, thoughtless and annoying, not criminal and even in our tiny Wyoming town the police probably had much better ways to spend their time.