A mighty bridge grows from toothpicks


The mighty Wooden Gate Bridge stands in the fifth-grade classroom at Eldersburg Elementary as a monument to engineering and tenacity.

Instead of concrete and steel, Wooden Gate Bridge is constructed of toothpicks and glue.

The Hammerjack team of four boys built the bridge from stringent job specifications. The boys purchased their materials from the mythical I. Saw Lumber Co. in the classroom.

Wooden Gate, about 30 centimeters long and 4 centimeters wide, accommodates a 3.5-centimeter-wide toy truck with room to spare. A 5-centimeter-high tall ship can sail under its trestles.

The bridge broke all previous records for strength.

"We even beat Liberty High School's bridge," said Peter Shaffer, 10, of the Hammerjack team, referring to a recent high school physics project. The Liberty High bridge, he said, "only held 77 pounds."

Eldersburg's effort didn't cave in under 80 pounds of weights.

"We started with 35 pounds and got up to 80, and it never broke," said Steven Fultz, the 11-year-old project director. "There was a 67-pound difference between first- and second-place bridges" in the elementary school's contest.

Nine fifth-grade teams at Eldersburg built bridges as a mathematics project. Only four withstood the stress tests.

The other five, said Steven, "either cracked or broke or the truck couldn't get through."

Steven kept a journal of what his group accomplished each day.

"Once, our side supports bent in," said Peter. "We ripped them off and started over."

Even a little blood spilled onto the project. A tiny dried drop stains the cardboard bridge mount.

"Chad [Parker] pricked his finger with a toothpick," said Peter.

No help from home was allowed. All pasting and piling was done in the classroom or the cafeteria.

"We live in the same neighborhood, so we could do the planning at home," said Daniel Moody, 10, the architect, whose job was to show the others how to build from those plans.

"If we had planned poorly, we would have built poorly."

The painstaking, often sticky, labor paid off as Wooden Gate withstood the final test: sand bag weights.

"It bowed a little during the strength-test competition," said Joan Hoffman, a math teacher. "After the weights were removed, though, it came right back to shape."

Economics also factored into the competition, said Peter. Each group was required to stay within a $1.5 million budget. The money went quickly at $1,000 per toothpick and $850 a day for glue.

It was "just the classroom variety glue, not the kind carpenters use to hold wood together," said Chad, 10, the carpenter. "Building is a lot of work."

He said that layering the nearly 1,000 toothpicks used in the 10-hour project reminded him of playing with Lincoln Logs or Legos.

"We couldn't take this bridge apart, though," said Peter. "The glue stuck to everything, too -- especially our hands."

"I had glue all over myself and toothpick pieces in my hair," said Daniel.

Wasteful spending caused more than one group's collapse, said Peter.

"We had to keep a careful balance sheet," said Peter, accountant and transportation chief. "We spent our money wisely and finished with $17,000 left over."

It was enough money to "fill in any weak spots" with extra toothpicks, he said.

"We concentrated on making our bridge strong, not making it good-looking," said Chad.

Building their own bridge gave the young Eldersburg engineers new respect for the profession.

Chad said he is considering an engineering career. He comes by it naturally, he said. His grandfather built bridges during World War II.

"This has been a good experience in what an engineer's job is like," he said.

Daniel said the project taught him the value of teamwork: "We didn't argue; we pulled together."

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