I think the more exciting takeaway from this is the Mastery Learning method causes a one sigma gain (from 50th to 84th percentile) for free whereas private tuto

I think the more exciting takeaway from this is the Mastery Learning method causes a one sigma gain (from 50th to 84th percentile) for free whereas private tutoring lets us gain another sigma (from 84th to 98th) for 10x-15x the tutoring cost. There’s also something else that’s driving my skepticism further. We know that deliberate practice works [1], and the possible effect size is much larger than two sigmas (think more like from a good chess player to grandmaster [2]). However, at this point the effects of both deliberate practice and tutoring start to blend in too much. The mastery learning aspect already seems like a methodology similar to deliberate practice. Does tutoring cause the additional sigma by letting more deliberate practice happen, or by some other vices? If we’re stuck with a 30-pupil classroom as a tutor, is it possible to extract those vices from private tutoring to help our class succeed? [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102783/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102783/ [2] http://slatestarcodex.com/2017/07/31/book-review-raise-a-genius/ http://slatestarcodex.com/2017/07/31/book-review-raise-a-gen...