One of the articles sourced by Snopes is this NYT article, which I think highlights one of the major problems with teaching:

Across all school subjects, teachers receive a pale imitation of the preparation, support and tools they need. … the overall picture is of a profession struggling to make the best of an impossible hand.

And across all subjects, the neglect shows in students’ work. In addition to misunderstanding math, American students also, on average, write weakly, read poorly, think unscientifically and grasp history only superficially.

Teachers almost universally bear the brunt of a toxic society from all sides. Children with poor behavior, Parents who promote it, Administrators who ignore it, and almost everyone incentivized by shit laws like No Child Left Behind to keep skating those kids through every step of the way - find any excuse to pass the problem child on to the next year, conjure any reason to get Brad that sports scholarship even though he can’t multiply fractions.

Our entire society has venerated ignorance for half a century, and we’ve become exceedingly efficient at it. Few places are as protective and proud of their bad reputation as the USA.