This is a great idea, but does need some more hand-holding and fine points. For example, chapter 3 goes into turtle graphics. Great. However, the book doesn't tell students they need to use the Repl.it Python-Turtle repl rather than the standard one they'd been using. Also, the 2nd example in chapter 3 attempts to set the title in the UI:

wn.title("Hello, Tess!")

This fails in Repl.it's turtle repl environment.