The lesson Liz Maatta had in mind to teach leadership skills in a classroom of children just a few years her junior involved a stack of colorful building blocks.

"You're going to construct an exact copy of an object made out of Legos," said Maatta, a senior at East Ridge High School in Woodbury. "The leader, which we chose from each group, will come look at the object -- which you can't touch -- and will go back and tell your group how to construct it."

Maatta and fellow East Ridge student Jori Cooper were teaching Bailey Elementary School second-grade students in "Youth Teaching Youth," a 4-H program that's gaining popularity in Washington County. Teams of high school students briefly teach at elementary schools, and the Legos lesson last week kept the students scurrying.

"It's an activity that illustrates trust," said Amber Shanahan, Washington County's 4-H program coordinator. "The point is the group has to trust their leader to bring back the right information."

Sponsored by University of Minnesota Extension, Youth Teaching Youth has been a staple in Dakota County 4-H for more than 20 years. It began in Washington County's 4-H program after a funding crisis in 2009, when county commissioners voted to end the $130,000 annual appropriation.

Dan Dolan, who chairs the Extension Committee in the county, turned to private sponsors to help fund a pilot program two years ago.

"It's become a real recruiting vehicle," Dolan said. "Less than half the kids teaching are 4-H members. You get kids who are thinking about teaching or doing social work or simply because their friends are doing it."

Teaching with Legos is one way 47 young mentors create lessons in the once-a-week, one-hour sessions taught to 735 elementary students. Shanahan said those numbers should grow before summer, as 60 high school students trained about 900 youths last year.

For second- and third-graders, Maatta and Cooper lead a basic curriculum such as character-building. For fourth- and fifth-graders, they teach subjects such as cyberbullying awareness and drug and alcohol prevention.

Bailey Elementary teacher Carrie Brasuhn sat to the side of her classroom and watched as they ran the show.

"They hear teachers and parents say these things all the time," said Brasuhn, who has taught for 29 years. "But to hear it from somebody a little bit older that they consider their peers -- I think it's pretty cool."

Maatta, who also coaches Woodbury youth soccer and helps out at local summer camps, said she joined the program because of her passion for helping children. "I felt like the second-graders really listened," she said. "They all want to participate. I think they really enjoyed it."

East Ridge, Park and Stillwater high school students take part in sessions that last three weeks at each elementary school. Established programs in other counties can last six to nine weeks.

"What's really so successful about this is kids look up to older kids," said Autumn Lehrke, a Washington County commissioner. "They see this high school student teaching them about good habits, they take it more than just a teacher teaching."

Lehrke, who was elected in 2010, vowed at that time to secure permanent 4-H funding. She said Youth Teaching Youth is a strong conduit for revenue, as it has bolstered 4-H enrollment numbers and become one of the fastest-growing programs in the county.

"We were at 525 [4-H kids] when the hammer fell on us," Dolan said. "We're sitting at 675 now."

Andrew Krammer is a University of Minnesota student on special assignment for the Star Tribune.