If you’re a parent or babysitter, you’re about to enter the gap between the end of camp and the beginning of school. Maybe you were smart enough to plan a trip, or maybe you’re trying to fill the time with local outings, which can cost as much as a vacation if you’re not careful. Here are some inexpensive ways to squeeze the most out of the season.

In an unusual new program funded by REI through the National Audobon Society, New Yorkers can exchange Prospect Park volunteer time for recording hours in a state-of-the-art new sound studio in the park’s Audobon Center.