The American Motorcyclist Association and Victory Sports offer information on kid?s dirt bike racing, as of 2015. Other sources for information include the National Motosport Association and the Rocky Mountain Motocross Association.
American Motorcyclist Association has multiple articles that offer information on kids dirt bike riding. The articles deal with tips for buying dirt bikes for kids, tips for parent coaching and ways to know when a child is ready for riding.
Victory Sports has a beginner's guide to motocross racing that gives information and advice for parents, kids and first time riders. The guide describes the practice techniques and safety gear recommended for young riders.