TIM GANNON PHOTO | Freshman Megan Brewer, right, works on building a bridge out of basswood Friday at the Long Island Science Center.

They started the year building rockets and now they’re building bridges.

And when they’re done with that, they will build catapults.

No, they are not reprising scenes from “Monty Python and the Holy Grail.”

These are ninth-grade students in Riverhead High School’s “Smart Physics” class, and their rockets, bridges and catapults are projects they’ve undertaken in conjunction with the Long Island Science Center in downtown Riverhead.

About 43 Riverhead freshmen are taking Regents physics, a class usually reserved for juniors and seniors, thanks in part to a grant from the National Science Foundation and Adelphi University. Those students have been doing physics projects once a week at the science center on West Main Street, according to teacher Greg Wallace. The grant seeks to get kids interested in science at an earlier age by using fun activities to illustrate the practical applications of physics. The students also competed in a Rube Goldberg “Mouse Trap” competition in December.

“We’ve been working with ideas of structural efficiency, and trying to make the strongest shapes. So we are working on the weight to weight-held ratio,” said science center instructor Leila Makdisi. “They are all using the same glue and the same wood, so that it’s really the structure that they create, rather than the materials they use, that’s important.”

The bridges are all made out of small pieces of basswood, a very light material. According to Mr. Wallace, they must all meet the same exact specifications: 15.75 inches long, 3.15 inches wide and 5.9 inches high.

Once the bridges are finished, the students determine how strong they are, or were, by hanging weights from them until they break.

“That’s going to be hard to see, because I worked really hard on this and it’s going to be smashed into pieces,” said student Kimikho O’Connor, shortly after completing her bridge.

Justine Kundmueller said it took about three hours to build her bridge. She said the project was fun, but not as much fun as making rockets.

This is the first year the students participated in the bridge building competition, and two of them, Matt Cutrone and Medarto Tores, qualified to compete in the Brookhaven National Lab Bridge Contest later this month. There also will be a bridge contest at the school for students not competing in the BNL contest.

Next up? Catapults. But they’re only little catapults.

Mr. Wallace said they will be capable of launching a marshmallow, although, he admitted, grapes would work, too.

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