I ran into the same confusion, but all the chord lessons are there. You have to make sure to click on the "Next" button found at the top of the lessons screen that you're in, rather than using the menu at the right of the screen. If you're in the "Simple C Major Chord" lesson then clicking on "Next" will bring you to the "Simple G Major Chord" and so on. Anyway, I think this is what you're talking about and hope it helps.