LeversBook - 2013
Readers learn how this simple machine makes it easier to lift, lower, and open things. They learn the three types of levers: first-class, second-class, and third-class. By the end of the book, readers know the difference between complex and simple machines and how levers are used in everyday life to make work easier.
Publisher: Mankato, Minn. : The Childs World, c2013.
Characteristics: 24 p. : col. ill. ; 21 x 25 cm.