It is a shame that calculators are stuck in the past for silly regulatory reasons, but there is a silver lining. These relics are excellent machines for learning low level programming without the complexity of modern hardware. You can write C code with essentially no operating system underneath you, read the keyboard I/O registers directly, flip pixels on the screen by writing to the framebuffer pointer, write your own interrupt handlers, etc. There are no other widely available computers this simple anymore, and because of their ubiquity there is still an active hobbyist community making new software.

If I was going to make a course on programming I would get every student a calculator and have them write some C on it.