As someone who has just got out of the curriculum that enforces usage of the TI calculators, given the ubiquity of these devices, I wish it was used more in teaching students about low-level programming, hardware, etc. especially with older models such as the TI-84+ there's great hacking potential. Compared to programming on the modern software stack, the Z80 is minimal. Plus, who said it has to be in assembly? Forth would do!
Some of my own hacking attempts:
[1] https://github.com/siraben/zkeme80/
[2] https://github.com/siraben/ti84-forth/