Can a boat made of aluminum foil hold a handful of marbles without sinking? What about a whole fistful? Our fifth graders set out to answer that question this week by building their own foil boats and putting them to the test.

Working in groups, students folded and shaped foil into three very different designs: a flat rectangle, a rounded bowl, and a pointed canoe. Then the real test began. One marble at a time, students loaded each boat while the whole group watched the waterline creep higher. Would the canoe sink? Would the bowl tip over?

Once the last boat went down, students compared their results and dug into the big question: Why did some shapes hold more than others? Groups shared their discoveries with each other, and more than a few were surprised by what they found.

It was science, engineering, and a little friendly competition all in one, and our fifth graders were floating on the fun.