National Curriculum offers 5 books which cover from the basics of horse health to riding and showing your horse and everything in between! The books are designed for grades 3-12. There is also a book for helpers of horse project youth.
Safe Horse Handling Techniques
WSU Publications offers a number of publications on a variety of horse topics.
What is the Purpose of a 4-H Livestock Project? (WSU)
Adult Horse Vaccinations
Equine Feedlease Agreements