In the Floating Boats unit, designed for grades 2-3, students are introduced to a real-world problem: a toy inventor has built a boat that sinks when too many animal figurines are loaded aboard. It’s up to the class to figure out why and invent a better solution.

Through a series of four hands-on, standards-aligned investigations, students test everyday objects to see which float and sink, explore how changing the shape of clay can make it stay afloat, and build simple models of rafts, canoes, and barges to determine how much weight each can hold. During this active research phase, just like scientists, they ask questions, test ideas, notice patterns, and share discoveries with their peers. These activities help students see how gravity pulls objects down, water pushes some objects up but not others, and small changes in shape or material can determine whether an object floats or sinks.

In the final five lessons, following the Engineering Design Process, children work in partnerships to design and build their own toy boats. Just like engineers, they brainstorm solutions, sketch ideas, build, and then test, refine, and present their creations. The final boats–made with bowls, trays, foil, and other everyday materials–not only hold weight without sinking but also showcase inventive ways of combining and reshaping materials, demonstrating how science understanding and creativity come together in students’ designs.