The boys from Halsted Middle School in Newton sent pumpkins weighing up to 15 pounds flying across a farmer's field and now want to build a smaller version of their device that they can take on the road.

"It's very fun. It's exciting," student Chris Perigo told the Newark (N.J.) Star-Ledger Wednesday. "Just the fact that we built this -- we're very proud of ourselves."

The trebuchet was a summer project for the young engineers who had been in the same technology class the previous school year. The Star-Ledger said teacher Jim Hofmann used the medieval weapon's design to demonstrate concepts such as tension, torsion and leverage.

Anthony and Heidi Lentini hosted the demonstration at their farm and footed the $1,200 bill for the construction of the trebuchet.