What do you do when you want to go out and you’re on a budget, but Grandma lives 2,000 miles away? Here’s one option: Start a babysitting co-op, an informal babysitting service organized with other parents in your neighborhood.

The gist: You watch their kids and they watch yours for free. “There are 15 members in my babysitting co-op,” says Betsy, a mom of one from Virginia. “We pay $15 per year to belong, which pays for the administrative costs of running the group such as copying medical forms and tip sheets on each kid. But otherwise the group runs on a point system. The more sitting you do, the more points you accumulate,” she explains. When members need a sitter, they call the secretary, who scouts for an available member. Members with the least points get called first. Secretarial duties rotate among members every two months. It’s an inexpensive way to get a little break.

For tips on how to start a babysitting co-op, see the National Network for Child Care.