Beth Harmon is fiction.
Her fictional chess teacher is terrible — teaching the wrong things, and in a backward fashion — which makes her rapid ascent even more remarkable.
Your children are not Beth Harmon. No one is Beth Harmon. Capablanca, on whom she is partly based, was a most extraordinary prodigy, but when he was Harmon’s age, he was just entering the view of the world, not yet capable of beating Lasker. Capablanca (born in 1888) thought he was ready to challenge Lasker in the mid- and late 1910s.
Technology and the inevitable march of time are making chess masters younger every year, and maybe if there’s a Harmon Boom, we’ll find a Beth Harmon, but my experience says it’s not your kid.
If you want a chess teacher for your kid, find one who teaches with a few units on the board as possible to begin. The first books I recommend to anyone are the Chess Camp series by Sukhin. Sukhin starts with a few pieces. Then he scrambles them in a different pattern, and scrambles them again. Then he adds a piece. And scrambles those. He does this is a layered fashion so the students will recognize patterns they’ve already learned in different settings as they go. Most remarkable books; I recommend them to players of any experience (I was a 2100 player when I typeset them, and they made me a better player).
Chess teachers like Shaibel, who begin with all 32 units on the board, are crooks. Do not waste your money on them, and believe me, almost all of them are like that. Grandmasters who teach “opening repertoires for all levels” are selling snake oil.
Mr. Shaibel the janitor was a terrible chess teacher. Your kid is not Beth Harmon.
I can see I’ll be saying that often from now on.