FOR USE IN SCHOOLS AND LIBRARIES ONLY. Covers the basic principles of money, commerce, and economics, and introduces emergent readers to the idea that everything has a comparative value. Simple examples are included.
Library Binding
(Lerner Publications TM, Aug. 1, 2015)
Is it easier to move heavy box with an inclined plane or wheels and axles? Readers will see how a group of kids compares two simple machines and decides which one does a better job at transporting the box. This book supports engineering design standards for primary grades in the Next Generation Science Standards.
Library Binding
(Lerner Publications TM, Aug. 1, 2012)
Learners will understand how saws have sharp teeth that cut through wood. A back matter spread explains how saws are a kind of simple machine: a wedge.