FortFourth

When a young child decides to build a fort in the backyard, Grandpa comes forward to help. But they can’t do it alone—they get help from the six simple machines: lever, pulley, inclined plane, wheel and axle, screw, and wedge. Told in cumulative rhyme, similar to The House That Jack Built, this story follows grandfather and grandchild as they build a fort together from start to finish.