What else is out there?
Researching direct competitors and other learning apps was a great way to see existing solutions.
Duolingo has progress indicators
In Duolingo the lessons change colors as you complete levels.
Duolingo has many options for leveling up
IXL is fun and colorful and the dashboard is distinct and clear
Course progress in IXL is measurable in several ways like this page showing all lessons with colored stars for completed tasks
Khan Academy displays the users courses in color coded sections on the dashboard
When choosing what to work on Khan highlights the section you are in and all available tasks