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.
Readers learn how this simple machine makes it easier to move things to different levels. They learn how flatter slopes use less effort than steeper slopes. By the end of the book, readers know the difference between complex and simple machines and how inclined planes are used in everyday life to make lifting and lowering objects easier.
