As I am working through the coding projects I thought it would be a nice feature to have checkboxes for each project so we can mark off user stories as we work through them. Also having the ability to go back to previous challenges to see what we submitted for the challenge. The flow of challenges seems to build off the previous challenge, sometimes I like to reference back to something that I learned only to find that the challenge resets as soon as you move on. A feature to save all completed challenges would be ideal.
This suggestion has already been made. See below for the discussion on Github.
It is recommended that you save your solutions as you complete them to your local computer and/or use Git to post them on Github. Then as you make changes to your solutions, you can see the entire evolution of your final solution, plus it allows potential employers to see how you solved various problems.