How about it?
Sunday, September 7 at noon. (The weekend after Labor Day weekend.)
Central Park toward the middle of the park but closer to the west side, just below the 72nd Street Drive (Terrace Drive). There's a green space bounded by fences, and with a bowl effect (so the kids won't be able to run away before we can get to them because gravity will slow them down). Close to bathrooms, and with background music (house and disco) from the rollerbladers.
To find the spot: Walk in to the park from 72nd Street on either side. Walk toward the middle, and follow the music from the rollerbladers (they're below the bandshell). There's a big ridge to the bordering the bladers on the west--the spot is right over that ridge. It is west of the rollerbladers, the bridge, the bandshell, and the mall. It is east of a huge pile of enormous rocks and the bowling/croquet fields. It is north of Mineral Springs Cafe and the Lilac Walk. It is south of the 72nd Street transverse.