Nearly two years ago, students in Mike O'Toole's science class at St. Xavier High School issued him a challenge.

The answer -- Mount Kilimanjaro.

So while students all over the country began their summers at the pool, 15 St. X students traveled to Africa last month to climb one of the world's tallest free-standing mountains.

Kilimanjaro sits on the border of Tanzania and Kenya, just south of the equator, and rises more than 15,000 feet from its base. But as the park's Web site notes, its summit is considered one of the most accessible among high mountains.

O'Toole said he had never led a field trip, let alone a bunch of students up a mountain.

"When you set out to do something, you might as well do it right," he joked when asked about the large scope of the trip.

With 12 family members and faculty chaperones, the students spent more than two weeks experiencing what they had only learned from books and other media before their "Xpedition."

The trip cost between $5,000 and $6,000 a person, O'Toole said.

They left Louisville June 1, reached the summit June 16 and returned June 19. Along the way, the group visited an orphanage and villages, and went on a safari.

"We picked Kilimanjaro because we had been talking in class about how the mountain and the people who live in the region around it really feel the effects of climate change," said Justin Coppola, who will be a junior at St. X. Justin's father, Carl Coppola, went along as a family member.

"We all thought it'd be a good excuse for an adventure," Justin, 16, said of the trip. "But then we were standing next to the glaciers that might not be there in a few years, and you really start to understand the impact. It's not just the glaciers either. The people we met there -- the climate change is really going to hurt them before it hurts us."

Before their trip, O'Toole and his students created a Web site about the mission. They noted how training was going, as well as listing information about what they would see and do in Africa.

From the beginning, O'Toole wanted the Xpedition to be about more than just a trip or vacation.

"The guys really bonded together on our training hikes and the group meetings," O'Toole said. "I wanted to make sure we worked in unity before and during. You put yourself in a very risky position on the mountain and you have to rely on each other."

Now, the group's challenge is to do something with what the members learned, O'Toole said.

He said he wants to use the Xpedition Web site to share the climbers' experiences in a way that educates people about global warming and other important issues.

Over the next several weeks, O'Toole said, he will add five-day curriculum plans for other teachers to use, journal entries from all of the Xpedition members and ways people can make a difference.

O'Toole said he understands that climate change and global warming are politically charged topics, but that doesn't mean young people shouldn't be educating themselves so they can draw their own conclusions.

"We're trying to create a way for students to learn about the science and issues and figure out what their opinions are and what they can do," he said.

Justin said his journey has affected the way he lives.

"It may sound really small, but things like leaving lights on when I'm not in the room really bother me now because I understand how that all ties into the problem of global warming," he said. "I also think that it might take some time before everything about the trip sinks in for me. What we did was the biggest thing I've ever done."

Reporter Sara Cunningham can be reached at (502) 582-4335.