I think the problem with lrns approach to teaching code is that it doesnt really force you to think or remember the specifics of the language syntax. If you want to learn to code you have to write actual code. In the absence of a JS interpreter, lrn needs to ask you to fill in more sections of code without multiple choice.
Dr. Missile about Lrn - Learn to code in HTML, CSS, Javascript, Ruby & Python, v1.4