Fishing for dinner in a river full of stingrays. Celebrating a maturation ceremony with an indigenous tribe. Witnessing Brazil’s land struggles firsthand.

Eight Massachusetts high school students returned to the United States Monday with unique stories to tell after spending two weeks in the ­Amazon.

The Wilbraham & Monson Academy students and their chaperones studied conservation, land issues, and two indigenous tribes in western Mato Grosso state, as well as how to catch dinner while avoiding stingrays, piranhas, and ­anacondas.

‘‘If you shuffle your feet, [the stingrays] go away, but I just screamed and ran away,’’ 16-year-old Jessica Smith said via phone from Pirenopolis, Brazil, on Friday.

The school’s dean of students, Brian Easler, first took students to Brazil in 2005 after his friend and environmentalist John Cain Carter told him conservation history was in the making in the Amazon, spokeswoman and chaperone Meghan Rothschild said.

‘I broke down, because it’s hard to see people in pain. The people need help, and the more people know, things will get better.’

Smith said the trip, the fourth by school students to the Amazon, was a ‘‘once-in-a-lifetime opportunity’’ for someone from a small town to live on a river and visit with members of native tribes.

The group entered one ­Kamayura village just in time to witness a coming-of-age ceremony.

There, a recent graduate and the chaperones received traditional Kamayura scratches, a form of administering medicine. The tribe warrior rakes the skin with a dog-fish-tooth comb, draws blood and rubs medicinal compounds into the wound.

‘‘We were treated like celebrities when we went there,’’ Smith said. ‘‘They, the kids, don’t really see people like us.’’

When the group arrived in a Xavante village, a handful of small fires were scattered around the tribe’s lands, echoing a scene from a Brazilian documentary on land struggles the class had watched.

As in the United States, ­indigenous groups in Brazil have fought squatters, landless workers, and ranchers, some of whom have lived in the area for decades, for access to their ­ancestral lands.

The group donated eight cows to the tribe, the village’s first source of meat in weeks, paid for by fund-raisers back home.

Arnelle Williams got choked up as she recalled entering the village for the first time, on her 17th birthday.

‘‘I broke down, because it’s hard to see people in pain,’’ she said. ‘‘The people need help, and the more people know, things will get better.’’

Although they have enjoyed their time abroad, the teenagers say they are looking forward to certain comforts of home, like pizza and manicures, after spending time in rivers and jungles. ‘‘We've been living pretty rustically,’’ Rothschild said.

Before 16-year-old Maria Slater jetted off to Brazil, someone told her she was too high-maintenance to survive the ­Amazon unscathed.

But the high school junior has traipsed through jungle, climbed waterfalls, and seen all sorts of creepy-crawlies, from frogs to scorpions to a tarantula.

‘‘I've learned that I'm tougher than I think I am,’’ she said. ‘‘At the end of the trip, I'm so much stronger than at the ­beginning.’’