I’m shocked that the US only adopted this in 2009. I’m pretty sure my mum, who went to primary school in the 70s, recognized number lines when I was taught to use them on 2005ish. I’m having a hard time imagining how else you’d explain it.
First you make them memorize single digit subtraction X - Y where X >= Y. Then you extend that to small double digit numbers.
Then you teach “borrowing”. 351-213. Subtract the 1s column. Can’t take 3 from 1, so borrow 10 from the 5 in the 10s column, making 11 in the 1s column and 4 in the 10s.
look, we work very hard on being reactionary here in the U.S., we’re a world leader in reactionary politics, and not teaching math well is crucial to keeping a vibrant slave worker population, otherwise they might start, you know, thinking for themselves
sort of like the reactionary trend of pulling your kids out of school because Common Core has changed how math is taught so critical thinking and conceptual understanding is incorporated, rather than teaching math by rote memorization?
I’m shocked that the US only adopted this in 2009. I’m pretty sure my mum, who went to primary school in the 70s, recognized number lines when I was taught to use them on 2005ish. I’m having a hard time imagining how else you’d explain it.
First you make them memorize single digit subtraction X - Y where X >= Y. Then you extend that to small double digit numbers.
Then you teach “borrowing”. 351-213. Subtract the 1s column. Can’t take 3 from 1, so borrow 10 from the 5 in the 10s column, making 11 in the 1s column and 4 in the 10s.
Definitely more clear, right?
look, we work very hard on being reactionary here in the U.S., we’re a world leader in reactionary politics, and not teaching math well is crucial to keeping a vibrant
slaveworker population, otherwise they might start, you know, thinking for themselves