Tandy 1000, parents sold it. Then TI-85 until a student I was tutoring stole it. Then a TI-86 and HP-48G, plus a high school CS class that used True BASIC on some kind of Macintosh, and by that point C++ and others on my PC at home.

But a lot of time in chemistry and on the school bus rides was spent programming on my calculators.

I ended up with a TI-86 as the cheaper ones were sold out at the time of the school supply rush.

It's the only reason I passed my math classes in high school. Luckily I kept my mouth shut so the teachers didn't know. Eventually they implemented a factory reset procedure on test day.

You would bring up the reset menu and the teacher would walk around and initiate it and confirm it.

Yep, TI-81 here

Ti84 here, basically the same