I don't know how you got your number but your math seems deeply flawed...
I don't think that's common. I especially don't think it was common ~45 years ago.
I graduated 35 years ago and back then was able to pay my MIT tuition by consulting over the summer + January. CS of course during the AI boom. Doubt that’s possible today.
I think the financing of education in the US is absurd and broken, but there is some logic to spreading the financing of an asset over the lifetime of the asset.
Some back-of-the-envelope math:
- K-12 enrollment in 2021 was 49.4MM [1]
- Assuming even distribution across 13 grades, that's 3.8MM / academic year.
- 1MM ~= 25%, though if one factors in that drop-outs increase as years advance, this is conservative.
[1] https://nces.ed.gov/fastfacts/display.asp?id=372#PK12-enroll...
[edit] formatting