Earlier quoted context omitted.
You're making a lot of leaps of logic here, which might be why your colleagues are disagreeing with you. You go from "not everyone can learn algebra or calculus" and "mental disabilities exist" to "therefore intelligence is a scale and controlled by genetics and unalterable," which doesn't really track. Your previous education, your upbringing, your cultural values, these things all also have huge effects on your apt…
I think the more people can learn algebra than OP implies, but as a former math educator my experience also indicates some people are genetically limited in mathematics. For reference, my specialty was working with very remedial students and only ever had a few students not make progress (~2%) but I do think that small percent was genuinely hopeless and I don't say that lightly. I have a pet theory as to why those st…
I got the feeling as a kid that a lot of my classmates would just give up. I mean they're sitting there acting like they're concentrating on math, but they aren't. In other classes intermittent attention is enough, you pick up social cues and repeated stories that you've heard, and poof you have a history essay. With math there's a need to have all the steps.
How do you control for that as a teacher observing the kids? How do you know whether a kid has actually tried to learn stuff at home?
I still remember my brother was baffled at how I got top grades in math when he never saw me studying. Of course I tended to do that when he wasn't around.