Last year I bought I used TI for my daughter who needed it for school. I got her the oldest version, the one which takes AAA batteries and communicates with the outside world through a serial link. A project like this brings to mind the possibility of stuffing a Raspberry Pi Zero in the battery compartment, hooking it up to the school WiFi, using a terminal app on the calculator to communicate with the Pi and in that way voiding the whole reason of using these ancient beasts in the first place. I won't do this of course - she's there to learn other things besides refining the art of cheating [1] - but it would be a tempting hack. An even more elaborate hack would be to replace the guts of the thing with a Zero running a TI emulator as well as some more useful stuff like ssh. The possibilities are endless... so endless in fact that I'm fairly certain this has been done already, somewhere.
[1] which in my days at school consisted of writing the translated works of Homer on a 10x10cm piece of paper, a good way to a) learn to write incredibly small and b) get those words to stick inside your head long enough so you don't actually need to consult the cheat "sheet" during the test.
[1] which in my days at school consisted of writing the translated works of Homer on a 10x10cm piece of paper, a good way to a) learn to write incredibly small and b) get those words to stick inside your head long enough so you don't actually need to consult the cheat "sheet" during the test.