This is what happened to me in middle school. I wrote a bunch of programs to “help” me with algebra II tests and ended up inadvertently learning an insanely marketable skill in the process.
Of course, nowadays all these TI calculators have exam mode, which blocks the internal memory and a bright LED to indicate this mode is enabled. And the older calculators, with practically the same feature-set (TI-83, TI-84) are now forbidden (should clarify still the same TI-8x calculators are allowed - but only if they have exam mode). Nothing is fun anymore these days.