- I bought him a Kano computer kit when he was about 7. The kit retailed for about $250 at the time and a kid could assemble it "like LEGO". It came with educational software that introduced him to programming languages, etc. (Unfortunately I do not think they make this kit anymore.) Verdict: MINOR SUCCESS.
- I tried to introduce him to Python (around 7.5) by following an online book about game programming. He did not show much interest. Verdict: FAILURE.
- I introduced him to MakeCode (arcade.makecode.com) around 8. He got absolutely hooked and it is still his favorite platform today. I bought him some cheap hardware (Meowbit) to put his programs on and he loves showing off his games to his friends and everyone else. Verdict: MAJOR SUCCESS.
- I introduced him to Godot when he was 9. He showed strong interest, built a few games in it and even understood enough of the Python like language that Godot has. He used this series of YouTube videos to learn about Godot: https://www.youtube.com/watch?v=HvPTSZl2WCc. Verdict: MEDIUM SUCCESS.
- We are currently building Ben Eater's 8-bit computer (eater.net/8bit) and he absolutely loves it. He is able to follow along with the videos and understand the material at a good level. He has named the computer "Terry". This project does require a lot of my own time. Verdict: MAJOR SUCCESS.
We have also tried other projects (e.g. Raspberry-pi with Raspbian, Arduino, Robotics kits, etc.) although nothing that he showed major interest at the time. I think you have to try with different things to see what will capture your child's imagination.