Please keep up the good work.
While print is exactly the medium I want for something of this sort, I do think it would be wise to look into some sort of digital subscription / supporter option.
I notice that you only sell print subscriptions. Do you plan on selling any digital-only subscriptions? I would sign up in a heartbeat because your online layout is Really That Good (TM).
Author approached learning mathematics in the same manner as learning a new foreign language (Russian), and it served her well.
Student focus on maintaining grades throughout school is sadly a detriment to slow learners who actually do need to spend the time to absorb, savour, play with and drill new concepts. I used to think I was a smart, but after years of successfully guessing the teacher's passwords[1] in class and on exams, I realized I only short-changed myself. Comparing against others with the benefit of age and hindsight, I realize now that I'm one of the slow learners who actually need an inordinately longer duration to thoroughly understand concepts than others.
MOOCs and other forms of self-study are great in this regard since pace-setting is now controllable, but rarely lead to a degree or credential one can leverage later in life. I'm glad that the author was able to apply her effective language learning approach to mathematics and science presumably within course durations (all the way to her PhD).
[1] http://lesswrong.com/lw/iq/guessing_the_teachers_password/