What permits would i have to get to hold a feild day in a local park? -

It is to raise money for the early ed and care program at my school. Like a senior project. We want to hold a feild day for the community kids but legally we need permits. but how many would i need and what are they called so i can start researching them? has anyone done this before? any advice? btw it is for kids 10 and under and because of the age we are making each parent sign a permission form when they bring their child to sign up and pay.

Your best bet is to go to your City Hall and ask them these same questions. They will tell you exactly who to talk to and where to get your required permits. They may even be available at the City Hall, where most municipal business is usually done.