Yes, there are restrooms at Pier 6 at Fornino, in the Boathouse in the Pier 5 Uplands, in the orange building on Pier 2, in Empire Stores, in 99 Plymouth, and seasonally at the Pier 1 entrance.
Yes. There are water fountains throughout Brooklyn Bridge Park and each has a water bottle filling feature.
Water fountains are turned off for the winter season when outside temperatures reach freezing.
Yes, however a permit is required. School trips and field days are allowed for a maximum group size of 200, with 1 adult present for every 10 children. Brooklyn Bridge Park has a limited number of school bus layover parking and is not guaranteed. Insurance is required for schools outside of the New York City public school system. Please see the permits page for more information.