If they can’t do basic grade school math, it’s probably safe to assume their entire education is extremely limited and they’re functionally illiterate. Like can’t balance their check book illiterate. So I wouldn’t expect them to have the rounded peripheral knowledge needed for a top tier education. Why would we want people with such poor educations teaching children?
You're confusing literacy with numeracy. To give you a counter-example to what you're saying, my son reads above grade level, but has math anxiety, and would struggle with some of the questions that mixed percents and fractions, especially on a timed test. If he decides he wants to teach, he'll be great at it, but he'll need to level up in math skill and get more comfortable with juggling numbers in his head.
Your comment about wanting better-educated people to teach is legit. But we have, in America at least, run-down areas with crappy primary schools. Some of those kids will feel a calling to teach. What should we do about that? Find resources to help them get to where they need to be, or tell them they're too dumb?
If they've finished college and plan on going into education and can't mix fractions and percents, then it has nothing to do with their primary school math scores.
Which is actually a much larger question - how are teachers graduating from university without being able to do 5th grade math?
So to become a teacher you have to complete either 36 or 72 hours of math education over a single 6 month period, even teaching math in grade 12. That's it. That's less than 2 hours of math per week over 6 months.
More scary is that it DOESN'T mention exams. There seems to be no need to actually remember anything. You have to complete "practicum" which seems to be 2 months of helping out a teacher in a classroom, and "more" in the second year.
