Sarah Wong knew exactly how fast she needed to drive her team's Formula One-looking vehicle - 24 minutes and 15 seconds - to get the best fuel efficiency out of it at this weekend's Shell Eco-marathon.

While Wong zipped around Discovery Green, Madison Jackson rattled off the work her classmates had done to get the lean, three-wheeled machine ready for competition.

"Everything that worked in the last four years, this is a mesh of it," said Jackson, whose team from Houston ISD's Westside High School competed against 79 other high schools and universities gathered in Houston over the weekend to see which could field the most fuel-efficient vehicles. They built the vehicle, which cost about $3,000, in their Engineering Design and Development class, Wong explained.

Her team, the "Wega Legends," focused on a different frame - aluminum instead of bamboo - from years past, Jackson said. They further modified it to make it more aerodynamic and added a roll bar, a floor and a bulkhead. Getting everything together didn't come easily, the 18-year-old said.

"It took a lot of hard work, and we didn't know our individual skills. ... Just seeing everyone work together was very hard, but once we got the kinks out, it looked good," she said, as engines from other competitors' teams cracked and revved behind her.

'A proud moment'

The car had already made a successful 6-mile run earlier in the day. "I'm so happy we got a whole run through," said teammate Anthony Foote, as Wong circled the track on the team's second run. "Seeing her do all 10 laps, it was just - we did it. We not only got it running, we got it running for six miles!"

"It was a proud moment," said Jackson, who plans to study petrochemical engineering at Texas A&M University next school year. Building the car, named "The Legend," was a learning experience, she said.

On their second attempt Saturday, Wong made five six-tenth circuits around Discovery Green without incident before disaster struck: part of the car's steering system gave way, forcing Wong to stop the run to keep from crashing.

"I'm glad I had a safe stop before anything happened," said Wong, 17, later, as she and her teammates surveyed the vehicle's innards.

Read this article:

Students drive to be stingiest in Eco-marathon