When Chinyere Oteh welcomed her first child in 2009, she found herself in a predicament familiar to many new stay-at-home mothers: Stress was high, but money and time were short.

“I thought to myself, I can’t be the only person trying to figure out how to have a healthy family life as well as make ends meet,” Oteh said. That’s when she remembered an article she had read on time-banking.

Time-banking is a model for trading skills, goods, and labor instead of money—a sort of barter system where members “deposit” hours doing things like teaching, cooking, or repairing things, and “withdraw” hours of other members’ services. It’s been around in the U.S. since the 1980s, and there are close to 500 such banks across the country today.

Oteh started small in 2010. She invited 10 friends in St. Louis to meet and gauge whether there was enough interest to start exchanging. Those who liked the idea invited more friends, and the group quickly grew to 25 people swapping things like lawn-mowing (Oteh’s first ask) for casseroles, mural-painting for help with cleaning. The goal was to improve their quality of life and show that neighbors can meet some needs without money—and that everyone has something to offer.

Oteh named the group Cowry Collective after the cowry shells once used as currency in Africa, China, and North America (and a throwback to her own West African and Ojibwe heritage). Each hour earned and exchanged is a “cowry”: You can use one cowry to get an hour of service from anyone else in the time bank.

The collective has 236 members, and more than 2,000 cowries have been exchanged (though Oteh estimates many more hours have gone unlogged).

Mary Densmore has been a member for three years and relies on other members to help farm her two small plots of urban land. Over the years, she’s exchanged services such as bike repairs and beekeeping lessons, but these days she usually sends helpers home with fresh food. Cowry Collective has helped her connect with new people and even changed the way she thinks.

“Often I’m [thinking], How much money am I making? That’s real, because I have bills to pay,” Densmore said. “But it’s not really about money—it’s cool to be able to produce something that is able to help me meet my needs.”