For the book, August and Mazin drew on hours of Scriptnotes conversations, as well as their own storied careers, to help readers begin, refine and sell their own scripts.

Raquel Figueroa-Crespo, 17, of New Haven, carries books to a Little Free Library in a garden next to Dr. Reginald Mayo Early Childhood School on Goffe Street in New Haven, Conn., Thursday, July 17, ...