I had a TI-99/4A. I learned to program from the excellent Basic manual that came with it. I wrote my code on paper, then keyed it in to run.
I mainly wrote basic games for my friends. Most popular was a two player competetive snakes variant, a bit like Tron but with traces only growing as you gobbled up food. I also wrote a 'defender' like game that enjoyed some success amongst friends.
I had no periperals or cartridges as that was too expensive. The living room TV was my monitor. It was quite a while before I got a cassette tape player, so in the early days a computer session started by retyping all code from my notebook.
I later got a ZX Spectrum which was far more powerfull, but the TI (and a HP41cv) are what got me into programming.
Oh yeah. I sort of forgot. The 99/4 came with some very decent manuals. I remember the Extended Basic manual being a bit "meh" compared to the regular 99/4 manuals, but I'm probably doing it a disservice. It was probably still a great manual.
I too learned a lot from that book.
It was not until years later I actually understood what I was doing. The little dancing guy was magic when I did it the first few times. Now I see it as a boring little program that loads up a bitmap into memory and then hangs out in a loop. I think the 'magic' may be gone :)