Nice, now he’s competing with you 
I started him coding at 3 or 4 with Scratch as soon as I’d taught him to type with some online typing app…
He was rote learning in China, so this was my way of opening up the creativity a bit more, one of his friend’s Dad’s was doing a lot on IoT back then, making connections through a language you don’t speak is hard, best done through your kids interests…
I bought a bunch of AI books (copied) off Amazon equiv there TaoBao and he read those up a bit What books would you recommend for learning Machine Learning from scratch? - #7 by phyde1001.
I used to do what he’s doing (but in my later teens), I’d race myself, new function per hour on a Treeview system… These projects are his hour or 2 each evening after school or over w/e… Built Phas on Command Line with PHP and later MASM, editor through notepad, error management… Teachers didn’t know much back then, maybe just some DTP…
Now I’m trying to teach him what I know but a bit more pro like @jochenschultz and @_j do it ^^…
His teachers still only know DTP 