James Holter 
Racing Dirt Bikes [PDF ebook] 

Motocross is the sport of racing motorcycles off-road. This book follows the riders as they complete several laps around a course of jumps, turns, hills, and bumps. After learning how to ride a dirt bike safely, many kids decide to race. Racing is tough, but with dedication, practice, and patience, anyone can become a dirt bike racer. Color photographs, a glossary, and exciting fact boxes will get your students ready to race.