Edgemont Memorial Park
One of the biggest playgrounds in the area along with Brookdale, this one provides plenty of structures to entertain your children. Including the great spider web structure, and plenty of slides, this playground is also fenced in. No permanent bathrooms, but there are 2 port-a-potties. Parking is on the street.
Make a Day of It: Explore Watchung Ave in Montclair, chock full of shops and restaurants. A quaint little café that serves crepes is on nearby Park St. called Bonjour Montclair. Only a few tables are outside in warmer weather, so snag a seat!