Get some fresh air and exercise by making a 5-K loop around the park with your brood. Participants will start at the bandshell and wend counter-clockwise down to the lake, around the zoo and finish near Center Drive. The event raises money for the park, so think about creating a fundraising page when you register online, and then ask family and friends to help you reach your goal. Enter at 15th St and Prospect Park West; registration begins at 9am, race begins at 10am. All ages.