Pebble plus. Mighty machines

Simple text and photographs present backhoes and the work they do.

Photographs and simple test in English and Spanish describe military helicopters, their parts, and their crews.

A simple, photographic introduction to submarines, explaining what they are, examining the different parts of a submarine, and discussing what subs do.

Photographs and simple text describe various farm tractors, their parts, and what they do.

Photographs and simple text describe naval destroyers and their purpose in the U.S. military.

Text and photographs introduce cranes, truck cranes, and tower cranes and how they life and raise loads high into the air.

Simple text and photographs describe tow trucks, their parts, and their jobs.