So I remember that this movie started with kids finishing school and summer vacation just started. It was about 3 best friends, who run out of school enjoying their freedom.

Also remember a scene in which they used a water gun on an older boy crotch to make him look like he peed himself. Also there was an old man in the neighbourhood, who was dirty and was collecting scrap, they were scared of him and I think their ball ended up in his yard.

Edit: I may have mixed up two movies with the idea of ball falling in a neighbours yard, as someone suggested the Sandlot.

However, if I'm not mixing in any more movies, I remember a scene where one of the boys crashed a girls doll house party with frogs (I think it was his little sister).