As modern teaching materials include an increasingly diverse array of digital formats, it becomes essential for teachers to easily and effectively share material with students online. We will introduce you to TeachBooks (our own TU Delft flavor of Jupyter Books), and how it can be an essential tool for collaborative and effective teaching. This presentation will introduce our community and challenge you to join. Whether you're a decision maker, programmer or (future) book author, anyone can contribute to an online book (really---all you need to be able to do is use a keyboard). Getting started with a template book for all your students and colleagues to see and interact with online takes only 10 clicks!