Rethinking what teachers do

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Of all the ideas we have forgotten from maths class, the most important to relearn - because it illuminates our most urgent challenges - is the difference between arithmetic and geometric progressions.

Maybe you recall. An arithmetic progression is a sequence in which the difference between numbers remains constant. For example, counting by twos: 1, 3, 5, 7 and so on. Each number adds two more.

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A version of this article appeared in the print edition of The Straits Times on February 15, 2019, with the headline Rethinking what teachers do. Subscribe