I am exploring Course F today and noticed a couple of things that appear to be errors.
1. In Lesson 2 at least one of the puzzles require nested loops before the video on nested loops.
2. In lesson 6 puzzle 13 the directions say the code will be saved in the next puzzle, but when you get to the next puzzle, the code has not saved.
3. In lesson 10, puzzle 8 there code requires a different brush thickness, but that isn't one of the available tools.