At Derby Downs, everything rolls down hill.
But sometimes, it isn’t always clear why one car rolls a little faster than another.
And so it was Saturday during the fifth annual Gravity Racing Challenge, a competition among schools that support STEM, the study of science, technology, engineering and mathematics.
The event was hosted by the International All-American Soap Box Derby and race sponsor, Time Warner Cable.
A record number of soap box racers — around 120 students from 50 or so schools — ignored the day’s incessant rain to finish what they started months ago.
Essentially, the science behind soap box racing is introduced in the classroom, where students design, study and build their own derby cars during the course of the academic year.
Saturday was the day to show off what they learned.
“This is something the kids can construct, test their theories and then see the results. This is the results day of what they’ve been working on all year long,” said Bobby Dinkins, director of marketing for the FirstEnergy All-American Soap Box Derby.
Perhaps no teens learned more than a handful of wood shop students from Louisville High School, who veered off the traditional soap box derby car by crafting a custom-designed vehicle in the open division.
Their unique three-wheeled vehicle — which resembles a recumbent bicycle — took part in five different engineering competitions, from racing to steering to braking.
“We literally welded the frame together from tube steel and started from bare metal. No kit,” said shop teacher and race coach Jeff Hoffman.
The team took its vehicle to another level not seen at Derby Downs: regenerating energy power from nothing other than what they could harness from the hill.
The vehicle captured 0.7 volts of power, allowing it to move on the power for 103 feet.
Louisville — whose team included Christian Bailey, Curtis Warga, Alex Saffran, Tyler Davis, Jacob Gord — competed against Westlake High School in the open division. Louisville won four of the five events.
About nine other schools failed to finish in time for Saturday’s events.
While traditional kit cars cost about $600, Louisville’s custom ride cost about $3,000, which was raised entirely through community donations. It took about 60 to 70 hours to build.
“I think the whole process — the engineering, the troubleshooting — the kids learned a lot,” Hoffman said. “The race itself was the icing on the cake.”