There is a $7 per car charge for day use of the beach and park.
There is lots of parking, nice picnic area with grills, a couple of different playgrounds, snack bar, and very clean and large bathrooms & changing rooms.
There is a different charging schedule for overnite camping and that can be booked & info can be found on ReserveAmerica's website. Overnite camping includes use of the beach/park; I live locally so just usually go for the day to hang out -- actually, I was there for 4 or so hours yesterday and it was absolutely gorgeous!!! Highly recommend! (Bring bikes, scooters, kayaks, etc -- great space for all of that)
Get quick answers from Glimmerglass State Park staff and past visitors.