If you're serious about hang gliding then you must understand that your flight school will only teach you the core basics. Hang gliding is a never ending learning exercise and having a good theoretical background is vital if you want to improve your game. Here's a list of some of the best books to get you started:
- Hang Gliding Training Manual by Dennis Pagen - will focus on core skills on how to fly a hang glider. Highly likely that this will be provided by your school as part of training course.
- Performance Flying by Dennis Pagen - covers more advanced topics beyond the basics on how to improve your game. For intermediate to advanced pilots.
- The Secrets of Champions by Dennis Pagen - book is a series of interviews with some of the best pilots in the world. Highly addictive read and offers a lot of tips that these pros use to be the best.
- Thermal Flying by Burkhard Martens - book focuses on developing thermalling skills. Even though it's written mostly from a paraglider's point of view, 95% of the information in the book is applicable to hang glider pilots only. What makes this book unique and highly recommended is the sheer number of visual diagrams and actual photos that show by example what the book is describing.
- Understanding the Sky by Dennis Pagen - probably the best book out there for learning about meteorology as it relates to soaring. A must read.
Most of these books can be ordered off USHPA store website