Jake Davenport used a homemade pulley to move a wooden car to the top of a ramp made from empty milk cartons and poster board.
Ben Webber pumped water through a plastic tube with a syringe, and the car zipped down the ramp.
"It took a lot of practice, but our ride is working pretty good now," Ben said after the test run. "We still need to add some stick buildings and bales of hay, but the ride works."
The "Huff and Puff" is an amusement park-style ride that the boys and five classmates created based on the children's book The True Story of the Three Little Pigs. The team of fourth- and fifth-graders from Homestead Wakefield Elementary School created the ride for a competition at the Baltimore Museum of Industry on March 17.
The Maryland Engineering Challenges began in 1991 as an effort to provide engineering projects for students in hopes of getting them interested in science, technology and math.
"We foresaw a problem in 20 years where we would have an extreme shortage of people entering engineering and technology careers," said Mike Shealey, the director of the Maryland Center for Career and Technology Education Studies at the Baltimore Museum of Industry. "And if we we're going to do something about that, we had to have children technologically literate."
Students create a written report that includes a summary of the book they selected, give an oral report, build the project according to guidelines, and demonstrate how their ride works.
The program is open to students in elementary to high school. At the elementary level, more than 300 teams from across Maryland selected from three categories: creating a theme park ride that carries at least four people and is based on a children's book; making a paper airplane; and designing a fast, open-topped sports car.
"Until this program started, science and technology organizations did a lot of things with high school students, but that's almost too late," Shealey said. "Now we have second-graders coming to the competitions telling us how they made changes to get better friction."
Two other Homestead teams picked the amusement park ride project. Using recycled items such as CDs, a coffee can, cups, lids and rubber bands, one team created a ride that works like a merry-go-round. Dubbed the Tasty Terror, the ride is based on the book If You Give A Pig A Pancake.
"We painted the base light brown, like a pancake," said fifth-grader Kyle Thomas, who worked on the project last year with another group. "Then we made a ramp so people can get on the pancake. It's a pretty good ride. I would go on it if it was real."
The third team used cups, old CDs and their cases, Popsicle sticks and other materials to make the "Froggy-Go-Round," based on the book The Frog Prince Continued.
Laura Huang joined the team because she thought it would be fun to design the ride.
"This has been very cool. We designed some very neat witches' houses," said Laura, pointing to her favorite, which had a witch's hat for a roof.
The experience taught the students how to apply math and science concepts they are learning in the classroom. For example, the team used a compass and a ruler to measure pieces to fit properly on the platform, Laura said. But they faced problems along the way.
"At first the frog carriage wouldn't go," she said. "Also, the carriages wouldn't move on the wood so we had to create a track. But we finally made it work."
Debbie Limpert, who teaches classes in the school's gifted and talented program, is the adviser for the Homestead teams. Limpert got involved with the program seven years ago and saw it as an opportunity to foster teamwork, highlight science and math, and allow the children to learn from one another.
"Each year I select the students I believe have the strongest math and science abilities," she said. "I basically solicit the students to gather trash and see how it can become something else."
The project typically involves plenty of trial and error.
"At first we tried to use fishing line to pull the car up the ramp, and it just didn't work," Ben said. "Then we tried another string that came apart. It was hard figuring our exactly what to use to make the ride work. But we did it."
And what the students learn goes beyond the academic lessons, Limpert said.
"When the kids work on one of these teams, they learn a lot of team-building skills," Limpert said. "They learn that one person can't dominate. They all have to participate equally to make it work."
Limpert said she, too, picked up a few lessons from the program. She has had to learn to let the kids do the projects themselves.
"The kids have to be really persistent to get their rides to work," said Limpert. "If I asked a lot of adults to do what the kids are doing, they would struggle, too. And in other cases the parents could easily fix the rides, but I don't allow that. But it's hard not to help."