In less than three weeks a group of students went from first hearing about a competition to winning it.

Physics students at Oak Harbor High School broke down into three teams and then designed and built trebuchets they used to place first, second and third in a state contest held May 12 at River’s Edge High School in Richland.

Trebuchets were conceived in the Middle Ages as war machines able to hurl heavy objects at castle walls.

The Oak Harbor students competed against eight other teams from throughout the state. The teams had to launch water balloons to a small backyard wading pool.

Cristina Carter, Ben Olson and Joey Grove teamed together to build their winning trebuchet comprised of a metal frame and a wooden arm.

In the two rounds they competed, they hit the pool 17 times out of 20 attempts.

The team scores were calculated by multiplying the amount of water that made it into the pool by the distance the balloons were thrown and then dividing it by the weight of the team’s trebuchet. Teams had 15 minutes to fire 10 water balloons during each round.

“They consistently put way more water in than everybody else,” physics teacher Charles Moser said.

Second place went to Chase Dowling, Dan Nichols and Shiloh Forney and third place went to Chuck Queeno, Tom Schroeder, Karl Rollin and Steve Nydam. While the first place team used metal in their design, the other two Oak Harbor teams made their devices out of wood.

Moser said the students were committed to building trebuchets on their own time since they didn’t have time in class to build them.

The students would stay after school to perfect their water-balloon-hurling weapon.

“They did the whole thing in less than three weeks,” Moser said.