In my experience, age of homes in the neighborhood approximately equals age of kids in the neighborhood, +- a few years. And that makes sense if you think of who is typically buying houses en masse as a group - new families. Now, I don't live somewhere like SF of NY where people cycle in and out, more cities of various sizes in the midwest and south.

My first house was built in the 40's. A few original owners existed, along with second owners. I noticed I guess people don't tend to move often. There were hardly any kids in the neighborhood.

Next house was built in 2009(this would have been 2018ish), and the neighborhood was packed full of kids.

Next house was built in the 80s. A lot of original owners, again, few kids.

Next house was built in 2012, this would have been 2021 - tons of kids

Next house built in mid 90s. This was 2022. Almost everyone in the neighborhood was the original owner, very few kids.

So, if my theory holds, if you want to find a neighborhood with a lot of kids, buy a midrange house in a ~5 year old neighborhood.

(and yes, I realize I've moved a lot).