The tenure system in higher education is supposed to insulate professors from political fashions, but that shouldn't matter as much in primary or secondary.
Why?
My original thinking was that the stuff that's being taught should be less controversial there; the political circumstances might make a big difference if you're teaching college students about Marxian political theory or Austrian economics or, say, genetic engineering, but primary- and secondary-school classes are supposed to be survey courses and their contents should be pretty much settled. That might not be a very good argument, though, considering the not-too-infrequent explosions in American political discourse over the likes of evolution or whateve...
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