Chris Lema has done a lot of research into creating learning management systems on the WordPress platform.
For those who are unaware of WordPress, it is reputed to be the platform on which something in the region of 20{5f90343551c95c1cd8d815abe76582cd7f3b06a4d52ee69a52e5ef37d2cdd564} of all websites are built.
Here Chris takes a look at LearnDash, comparing it with WP Courseware which he has used to a much greater degree.
Click here to read more on his site.