ROY -- As pumpkins were loaded into homemade trebuchets, launched into the air, and obliterated by the earth, students shivered in their Viking helmets and Scottish kilts and worried about their grades.
Trebuchets, physics, medieval warfare and pumpkins all contributed to a memorable learning experience for a trio of ninth-grade physics classes at Roy Junior High School.
Only a handful of the orange bombs were hurled beyond 30 feet before smashing into pieces on the grassy soccer field, but physics teacher Lynn McMillen felt the students learned a fair amount in the process.
"We have seen some successes and some failures ... but they have learned to interact with other students, listen to others' ideas and come up with a design," said McMillen, who has developed the trebuchet project into a 10-year tradition. "I like the ingenuity you see. They go find scrap stuff and put it together, they use their mind."
Students had two months to work on the project in groups of four. They were required to design and build a fully functional trebuchet for $40 or less. A trebuchet, like a catapult, was used during the Middle Ages to fling large projectiles at high speeds into enemy fortifications. On occasion, disease-infected corpses were flung into cities in an attempt to infect or terrorize the people under siege -- a medieval form of biological warfare.
Once the contraption was assembled, each team was supposed to execute 10 test runs to work out the bugs. It was clear Thursday that some had skipped that critical step. To receive maximum points, a team's pumpkin needed to fly at least 32 feet. The students also had to write a detailed report explaining the physics of the project.
Fortunately for some students, McMillen said they could dress up for extra credit.
The project has unintentionally become a battle of the sexes, McMillen said. An all-girls team set the school record for pumpkin flinging -- 96 feet -- about four years ago. An all-girls team also had the best toss Thursday, 65 feet.
"It's the girls that rock -- I don't know why -- they have something to prove," McMillen said. "It's usually the girls who start right away. The boys are the procrastinators and it bites them in the butt."
Riley Thiel, Montana Reed, Marina Brown and Breanna Burton were the all-girls team with the best mark. They welded their trebuchet from metal and painted it black. They huddled together, cheered and giggled when the pumpkin exploded.
"The best part is just seeing it succeed," the group agreed.
Some parents came to watch the grand finale, lining up behind the metal and wooden structures, most of which were 6 feet to 8 feet high. Todd and Debbie Vigil enjoyed watching their son, Zach, and his friends build the machine.
"It was fun to see what they accomplished. You can't believe how excited they were -- that's the neatest part," Todd Vigil said.