Trade school supplies for free beer

What Mighty Writers is hosting an event with Dock Street Brewery that lets people bring in used books or show receipt of a donation of at least $10 to Mighty Writers in exchange for a pour of rare Dock Street Beer.
Where Dock St. Brewery at 701 S. 50th Street
When September 6, 2017 at 3:00 pm to 11:00 pm
How much Free