NAUTA, Peru — On a muddy street in this muggy jungle town, Julia  Ipushima Manihuari has turned an overgrown play area into a classroom.

"Tsakama," she says, stroking a tree branch as a dozen children repeat the word in unison.

"What's this?" she asks, touching a leaf. The kids consult their notebooks.

"Tsa," they reply hesitantly, and she makes them repeat the word several times.

Pointing to the treetop, she says, "Suzapira." Except that the last vowel is somewhere between and "i" and a "u" -- it is written as an "i" with a crossbar -- and the children, accustomed to the crisp vowel sounds of Spanish, have trouble with it, trying the odd sound over and over.

The children are Kukama Indians who are discovering their families' native tongue -- a language they never learned at home -- at the Ikuari  School, a pilot program launched by Radio Ucamara, a station operated by the Catholic Church's Apostolic Vicariate of Iquitos.

By June, the school had 60 students, ages 5-14, and half a dozen teachers, but it faces a funding crisis and its future is uncertain.

The teachers are of the generation of the students' grandparents. As small children, they learned the language at home, but they faced scorn or punishment for using it when they started school.

"They punished us for speaking it. They told us, 'That's the language of Indians,'" says Victor Canayo Pacaya, 62, who team teaches with Ipushima. "When we were young, we tried to forget Kukama, but it stayed engraved in our minds."

The story is common among indigenous peoples in the Americas, but has particularly painful overtones in this region of the northeastern Peruvian Amazon, where indigenous communities were forcibly relocated and enslaved by rubber barons.

The Kukama who lived near the Huallaga and Maranon rivers adapted,  learning Spanish in an effort to reduce the discrimination they suffered.

"The language was disappearing," says Canayo, who spoke only Spanish at home with his own children. "No one wanted to be Kukama."

Among the few people who encouraged adults to remember and use their native tongue were the Augustinian missionaries in this town, which has grown in recent decades with a steady flow of migrants from indigenous communities along tributaries of the Amazon River.

A few years ago, a few of the older adults took to airwaves on Radio Ucamara with an early morning talk show, Kasita Kumitsa, which means "I want to speak."

The first program was nerve-wracking for Hilda Ahuanari Tamani, 73, who started speaking Kukama openly again when she was 65.

"I didn't know what I was going to talk about. I didn't sleep at all the night before," she recalls.

The shyness quickly wore off, as they discussed traditional remedies for health problems.

"We talk about spirituality, about plants and animals, health and the spirits that live in the rivers and lakes," Canayo says.

Last year, the talk-show hosts became teachers, as the radio station began offering Kukama language classes, first for bilingual teachers, but now exclusively for children, who learn through songs, games, stories and hands-on sessions like the one with the tree.

The effort to revive Kukama got a boost last year with "Kumbarikira," a  music video in which Kukama children sing a traditional song about a bird and rap -- their own creation -- about how cool it is to speak Kukama: The soundtrack -- probably the  first ever in Kukama -- quickly won fans here and in nearby Iquitos, Peru's largest Amazonian city.

While some of her friends ignored it, others wanted to learn the words,  says Danna Tello Morey, 14, the daughter of Radio Ucamara director Leonardo Tello and one of the singers in the music video.

She and other students say they became curious about the language when they heard their grandparents speak and wanted to know what they were saying.

Both the students and teachers hope the classes can continue, but Peru's Education Ministry cut back on promised funding, and Ikuari's future is uncertain. Manuel Grandez, director of intercultural and bilingual education, said the school is not a regular budget item, so the ministry's funding possibilities are limited.

"A lot of people want to learn to speak Kukama now," says Canayo, who is also teaching his own grandchildren, ages 4 and 7.

"When I'm gone," he says, "they're going to replace me on the radio program."