MILLVILLE — On any other day, catapulting small pumpkins across the Millville High School soccer field might be grounds for disciplinary action.
On Monday, it was a class project for students in Jamie Burrows’ Computer Assisted Design and Drafting (CADD) II class and Mike Dobrosky’s Woodworking II class who collaborated to design, build and test catapults.
School administrators even looked on approvingly, if cautiously, as pumpkins flew, dropped and rolled.
“This is what project-based learning is all about,” said Barb Blahut, chair of the Career and Technology Education department, as four teams of students discussed and adjusted their strategy for the two competitions — one judging distance, the other accuracy.
The CADD students spent about two weeks researching and designing their catapults, experimenting with software including A+CAD, SolidWorks and Google SketchUp. Then, they got together with the wood-shop students to build their designs.
Both groups quickly learned that what looks good on paper doesn’t always work in reality.
“We had to modify it quite a bit,” said Robert Shelton, 18, a wood-shop student. “The design was good, but not completely accurate.”
“(Ms. Burrows) told us this would happen,” said CADD student Michael Sharp, 16, who also learned to work with the grain of the wood, not against it.
Zac Brown, 17, said the team’s original design was very streamlined, but they soon realized the base wouldn’t be strong or stable enough.
“It looked really nice,” he said, “but we had to add more support.”
Three teams chose to build a traditional tension catapult and one chose a trebuchet, which works with a counterbalance.
“We wanted to be different and it looked cool,” Josh Garrett, 18, said of the trebuchet. Team member Bryan Hogan had built a smaller version and had some experience with them.
On its first two tries the pumpkin fell out of the trebuchet’s sling before it could launch, but on the third try it sailed the farthest — almost 90 feet. The team had similar problems on the accuracy test, and never got a pumpkin into the air. Team members said they had thought about allowing the entire sling to break loose, but they were concerned about safety.
For the accuracy test, students got points based on how close they got to a hula hoop. There was some debate among students about whether having the pumpkin land in the hoop, then roll out, was worth more points than having it land outside the hoop, then roll in.
Dobrosky said what he valued most was the communication and problem-solving skills the two classes had to use to successfully complete their projects.
“We (the teachers) didn’t interfere at all, as long as what they were doing was safe,” Dobrosky said. “We wanted them to figure it out themselves.”
Burrows said her students also had to do a PowerPoint presentation on their project, and research the history and physics of catapults.
“We had a discussion of force and tension,” she said. “And, we’ll be doing a bridge project where they have to build a bridge and calculate how much weight it will hold.”
Wood-shop students learned that while paper designs may need changes, they do provide crucial guidance.
“A little change can make a big difference,” said wood-shop student Marshall Crump, 17. “Math was key to the project,”
Dobrosky loved hearing that comment.
“They come into wood shop and really don’t realize how much math there is,” he said.
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