A day in early August 2014. The sun is strong, and the thought of school is far enough away to be a dream. A dozen Lakota girls from Pine Ridge Reservation in South Dakota make their way to a site called Coyote Springs. It’s 30 minutes from the nearest town, down a winding dirt path lined with prairie grass. It’s sacred land, and the house they’re headed to is the only building for miles.

Each summer, elder Inila Wakan Janis and his wife, Jennifer Janis, a teacher at the local middle school, present a math camp there for the girls. It’s a way to keep them up with studies during the summer as well as a chance to imprint the spiritual and cultural practices of their people.

After completing a math worksheet and eating a lunch of roasted squash and zucchini grown next to the house, 12-year-old Santana Janis is the first to climb into the creaky old metal pool that’s set up beside the house. She and the other girls splash around, do underwater flips before tumbling out, running back to the house covered in grass.

Next stop is the inipi, a domed sweat lodge made of branches and native grasses, covered in tarps and quilts to keep in the heat. Inside, the girls remember their ancestors, following Inila Wakan Janis in a memorial song for an elder who recently passed away.