Therese M. Shea 
Tractors [PDF ebook] 

Tractors may be slow on roads, but don’t be fooled. They’re mighty machines specially made to pull extremely heavy loads as well as provide power to farm equipment. Readers will love learning about one of their favorite big machines in the bright pages of this motivating volume. The friendly, accessible text and fun fact boxes are carefully paired with vivid photographs of tractors in action. An attention-grabbing concluding activity reinforces key ideas for both future farmers and mechanical engineers.