I did a search here and could not find anything recent. I did find a document on the parks department website that stated it was prohibited except by law enforcement.
I saw no signs on the building when I was there last, but have to admit I wasn't particularly looking for them either. I was CC'ing at the time, and would have ignored any silly signs anyway. I also didn't see any evidence of a licensed daycare or school-related anything while I was there.
Been there for packet pickup for Carmel marathon and looked around for licensed daycare since I wasn't sure how up to date the website is and didn't see anything, nor have I noticed signs