> (just a hypothetical, I assume most parents can't afford to buy one)

It used to be that high school students were required to have a graphing calculator. These had to be purchased by the student (iow by their parents) and without factoring in 20+ years of inflation costed more than some Chromebooks available today. I suspect there were (and still are) financial assistance programs as i've known students living below the poverty line and they were able to meet that requirement.