Sadly, HS girls BB participation has declined by 10% in the last decade. It's declining faster than tackle football(!). In that same span, volleyball is up 12% and soccer 14%,
I have my own theory as to why: HS sports are getting expensive. Most schools now charge for participation - in my home town, it's $150/sport. Plus players are increasingly expected to join youth teams, which are not cheap. Basketball is particularly popular with the poorer demographic - and I think these kids are getting squeezed out by the cost. Boys basketball is also down about 1% - I imagine that families are a little more willing to spend to get their boys into sports than their girls.
That's just my gut feel, partly based on the statistics and partly based on what I saw as my kids went through school with a large "disadvantaged" population.
Source:
While football and girls basketball fall, many other sports rise. But declining birth rates and demographic changes could result in more changes.
www.forbes.com