Funny, but we chose a different school than Exeter for our child partially because of concerns that pure Harkness would be a risk for high-level math. We were afraid our child might not understand advanced concepts clearly if class were only discussion-based, even though he/she has high ability in mathematics. I know that Exeter has an excellent reputation for mathematics, but several other boarding schools are likely in the same ballpark in quality of mathematics teachers and students, with a mixed mode of instruction that is lower risk, in my opinion.
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