I started my daughter when she was 4. I would recommend something the child can touch over abstractions. The Learning Resources Code & Go Robot Mouse Activity

I started my daughter when she was 4. I would recommend something the child can touch over abstractions. The Learning Resources Code & Go Robot Mouse Activity Set is what I started with. You setup a different maze and place the cheese on the maze. The child will program the mouse to navigate the maze using simple arrows on the top of the mouse. I have used other toys like the game Thinkfun Rush Hour Jr get them to start thinking about how to solve problems. If you must start with a screen, I would recommend Scratch Jr. There is a small book that has lessons building up to a project that you can use. My daughter picked up Scratch Jr after using it for about 10 minutes. The Microsoft store in the mall had a free course for 6-8 year olds, but it is not as interesting. I think Scratch Jr is better. I recently tried a pair exercise building a game with her using Scratch 2.0, but I think it is still too early.