The most success i've had with my 8 year old is building games in Roblox and the LUA scripting that comes along with that. We also have written some MicroPython to drive a small rover. With kids, or my kids at least, you have to be able to show some tangible results quickly or else they get bored. ...kind of like dealing with your boss.

another thing that my 8 year old is really into that surprised me is networks. Explaining how networks work and how he can start a minecraft server for him and his brother to play but his school friends can't because of the "firewall" has him on the edge of his seat hah.

edit: i want to add that i don't bother with explaining programming concepts like object-oriented design or algorithms just very simple cause/effect. Then to simple if condition effect. I get excited and end up overcommunicating and then boring my kids, it's like trying to start a carbureted engine without flooding it. You have to do give them just enough info to get started and hope it catches.