https://everykidinapark.gov/ -If you have a child in the 4th grade, your family is eligible for a Free 1 year National Parks Annual Pass. If you visit a site that charges entrance fees per person— The pass admits all children under 16 and up to three adults for free. If your group visits a site that charges vehicle entrance fees – The pass admits all children under 16 and all adults in up to one passenger vehicle-update – this program is   available again this year.