Good sentence, but what does this have to do with places?
Hey, at least is not something like "the little boy and the dog are playing next to the park in the old city, while the kindergarten teacher watches over him while jumping from one of the buildings and landing on the water, then walks on it."
The small boy and the dog are playing.
Is small okay to use here?
"Little boy" is more appropriate. It's about a certain age group, a boy younger than 10-12 years.