I would like to suggest putting a NEXT button...and...a RETURN TO MENU button at the bottom of each lesson on the UNIT page (in the MODULES section), giving the student a choice of what to do next.
The way it currently is, a student does a lesson in a unit, then has to back out to the main menu, remember which one was just completed (from a very long list) and then scroll down the list to click on whatever comes next. It is very cumbersome.
Thank you for your consideration.