Sounds like you mean "mixed" in terms of ages. My kids never went to school here but, from my perspective, most of the areas around SK are a good mix of families with and without kids.
But - one of my colleagues lives in an area where there are many families with kids and they share play areas and there's lots of opportunity for interaction between kids. That area is the new part of Leung Mei Village (up Chuk Yeung Road, past Jade Villas). I'm sure there are more like this. If you'd like to talk to her - send me a private email and I'll give you her email details (she's offered this).
Judy at Explore Sai Kung