Yes, it's very good. Math Academy is much more dense and on-point that Khan's. You don't have to sit through 15 minutes of video when 2 minutes worth of text e

Yes, it's very good. Math Academy is much more dense and on-point that Khan's. You don't have to sit through 15 minutes of video when 2 minutes worth of text explanation does it. It uses spaced repetition for topics that you aren't good at, and for recently learned subjects. The topic dependency tree and automatic progressing to "unlocked" topics is obvious in retrospect, but here it's done very cleanly and unobtrusively. The initial evaluation test is worth its weight in gold. It eliminates the need to grind through things that you already know, but still covers any gaps. I had kids on Khan for few weeks and it was a hassle. The pace was too slow, too much time sunk into trivialities and they were bored most of the time. With Math Academy they sit down, they do their 20-30 min of focused hands-on effort and they are done for the day.