Before Iredell students could leave school for summer, they had to spend a day at the pool, but this was ordinary day of soaking up the sun.

At the end of each year, seventh through twelfth grades construct a boat made entirely from cardboard and duct tape, then put it to the test in a series of competitions at Tarleton State University's swimming pool.

"It is a day of extreme fun, as well as frustration for some, and lots of smiles," said Iredell teacher Christine Coffell.

Students began the experiment in the classroom constructing scale models of boats using notebook paper and sinker weights.

"This activity is very rich in mathematical content," said Coffell. "They calculate the volume of their boats, surface area, perimeter of the top rim and, of course, the total mass held by the boat."

Students then traveled to the Tarleton campus to piece together the boats.

Teams of three each received two sheets of cardboard, two rolls of duct tape, a box blade, pencil and measuring tape. They then have two hours to build a boat that will pass a preliminary float test ensuring their vessel can hold two people for at least two minutes without sinking.

After that, students have a speed race and weight challenge keeping careful record of measurements the whole time.

"Students then compare and graph the data using a scatter plot to see if there is any type of correlation, which hopefully they discovered there is," Coffell said.

The math equations lay the ground work for more complicated physics and buoyancy calculations.