GREENVILLE, Ala. — Toward the end of a math lesson on a sunny Friday in October, fourth-grade teacher D’Atra Howard and math instructional coach LaVeda Gray ducked out of the classroom to huddle.

LEHI, Utah — It was the last class before Thanksgiving break, and high school math teacher Sarah Gale was dishing out more than her usual lessons on data science. “I can smell it,” said one student, ...