The Knoxville Public Library is hosting a special guest tomorrow as part of RAGBRAI. Matt Fritzinger is the founder of the National Interscholastic Cycling Association. It’s an organization that develops high school mountain biking programs across America to promote teamwork, professionalism, and the sport of mountain biking. There will be a screening of his documentary called “Singletrack High: A Film About Kids who Ride,” and he’ll do a question and answer session after the screening. That screening starts at 2pm at the Library.