Screws (Simple Machine Science)

The answers to what screws are, why we need them, and many more are, provided for curious readers. Screws help change a turning motion into an up-and-down movement. Screws, nuts, and bolts help keep many items in our world together. Readers will gain a valuable understanding of these simple machines through accessible text and colorful photographs. A comprehensive glossary and eye-catching graphic organizer aid readers in their exploration of these important science concepts. Looks at how screws make work easier, citing such examples as drill bits, car jacks, and water screws