We've all learned that writing tests before code is a great way to develop software. It turns out that it's also a great way to learn how to develop software in the first place! In this talk we discuss a number of projects that have used test-first approaches to teach Ruby, including Ruby Koans, RailsBridge Workshops, Wolfram Arnold's BFT (behavior-first teaching), Blazing Cloud JavaScript and Rails classes, plus our own open-source Learn Ruby TFT (test-first teaching) curriculum (at testfirst.org). Come hear about our experiences or share your own.