[marttt]

I've been thinking about starting with Computer Science Unplugged when our kids reach that age: https://www.csunplugged.org/en/

My idea is to keep children off screen addiction for as long as possible, whilst still teaching them the relevant mindset, patterns of reasoning, and the way computers actually work.

On another angle, my son did start throwing together maps and sprites in no time with the (Lua-based) TIC-80 and Pico-8 when I showed these to him. Load81 by antirez is a similar Lua environment without the constraints: https://github.com/antirez/load81

Or, why not put together a low-cost computer/Z80-like terminal with your son, like the RC2014 that runs BASIC: https://rc2014.co.uk/

Good luck!