[scryder]

Codecademy's model tends to be very poor for topics that are sufficienty theoretically complex, as the turnaround time between exercise beginning and conclusion appears to be about 5 minutes for non-project work.

Repetition/drilling for understanding and examination of knowledge by self-testing are wholly absent.

Projects like "free code camp" can dodge this problem because the staff is working for free as an open source project, but it would take a lot more 5 minute segments to teach someone linear algebra, the theory behind any type of model, and the background information that is necessary to generate provably compelling insight than companies like Codeacademy seem interested in tackling.