In general, schools do not specialize, and curriculums are designed to be entry level. I wouldn't put too much on clinical or even in class opportunities because their existence doesn't mean you'll get them. By this I mean, your school might have research projects or class projects on a peds case, but it isn't guaranteed you'll get that opportunity. Same goes for clinical experiences, just because a school has an affiliation doesn't mean they have open slots every rotation. That being said, a few things to make sure you are around peds knowledge-
1) Residency programs. A school with a residency program in peds is probably well connected.
ABPTRFE
2) Faculty research. See who is involved in peds research
3) Clinical practice within school? By this I mean, is their a clinic affiliated with your school that treats kids
4) Location: In general, big cities are more likely to have children's hospitals, which increases connections.
Lastly, realize that a lot of people who come into PT school thinking they know what they want change their minds. I therefore wouldn't let this be the sole determining factor of choosing schools, as you will learn essentially the same peds curriculum everywhere. Also, make sure in your app that you don't seem "peds and nothing else" as that can be a red flag for admissions.