Alison Cochrane wanted to give her students a project that combined science, technology, engineering and math in a way that made them think.

So the eighth-grade science teacher at Carl C. Cutler Middle School in Groton divided the class into groups of four. They would work like “companies,” she explained. Each had to design and build a bridge out of toothpicks and glue.

The kids could pick any style of bridge and location in the area of the Thames River, but there was a catch: each model bridge had to span at least 35 centimeters, hold real weight, and stay within a $1.5 million budget.

Toothpicks cost $10,000 each. Glue cost money also, as did engineering assistance. If the company wanted to ask Cochrane a question, they have to pay her, like a consultant. She charged $50 a minute.

Students hoped for a few freebies, so they’d ask, “Are you feeling generous today?” And she’d say, no, not particularly. Then the students would have to find the answer themselves or pony up the money.

Since the project ended, Cochrane has heard from teachers as far away as Canada, after the lesson was featured in the December 2014 issue of Science Scope, a peer-reviewed journal for middle and junior high school science teachers published by the National Science Teachers Association.

Groton Superintendent Michael Graner told the Board of Education recently that Cochrane’s lesson served as an example of how future instruction might look under the Next Generation Science Standards. The standards spell out the ideas, skills, concepts and practices that students in kindergarten through grade 12 should be able to know and apply in science.

Jake Browne, student teacher in Cochrane’s class since the end of January, said he watched the end of the bridge lesson, where students tested their creations with weight.

“No bridges looked alike, even between the classes,” Browne said.

Cochrane is in her seventh year at Cutler Middle and previously taught in Salem, Canterbury and Springfield, Mass. She’s always taught middle school science.

“I love it,” she said. “I love (the students’) energy, I love their attitude. I don’t see how anybody could be in a bad mood in a middle school.”

She had a bridge building project in prior years, but it was more basic. Students simply had to choose a type of bridge and build it. But after reading the new science standards, she realized the lesson had to go further.

All 78 students in her four classes participated in the project, which was done entirely in school.

First, she grouped the students paying attention to their individual skills, pairing mathematically-minded kids with others who might be strong writers or speakers. She gave each company an enlarged map of the local area showing streets and topography, then instructed the companies to choose a beam, arch or suspension bridge and explain where they’d build it. Students had to “hire” different engineers depending on the bridge; a civil engineer would know about environmental law, for example.

Once plans and designs were complete, each company “bought” their materials, hired workers from the various trades and started construction on a piece of foam board.

Jazzy Henderson, 14, was in charge of money for her group.

“I was the one who wrote the checks and figured out how much we spent,” she said. “I could tell when we were spending too much.” Cochrane served as auditor and checked each of the companies’ books.

Students also wrote a history of their bridge, explaining its location and reason for its design. Finally, they built the bridge and presented the project to the class, answering questions from classmates like, “How many people can be on the bridge at the same time?”

Then the students tested the bridges with weight.

Some folded up like fly traps, Browne said.

“Some of them just exploded,” Cochrane said. “It was loud, there was ‘crack’ and that was all she wrote. And they loved that.”

Others held many pounds, however.

Oliver Banks, 13, helped build the winning bridge, which cost $725,000 and held 15 pounds.

He and his classmates dropped a large rock on the bridge to find out its breaking point, Oliver said. “It cracked because we used so much glue,” he said.

Cochrane said the hardest part of the lesson was not jumping in when she wanted to help. But she knew it had worked, when the class started talking about engineering in a different context a few weeks later.

Now she thinks she might make the bridge project a little tougher.

“Next year, I think I’m going to cut the budget a bit,” she said.

d.straszheim@theday.com

Twitter: @DStraszheim