I helped out with a coder dojo where we used Scratch to teach kids to code. In that setting the biggest barrier was the parents getting in the way of their kids

I helped out with a coder dojo where we used Scratch to teach kids to code. In that setting the biggest barrier was the parents getting in the way of their kids natural exploring. Solve that and you can basically just put a kid in front of scratch and expect them to be productive on their own within a few minutes. Just be there to help them get unstuck. A pre made lab can be helpful though. Most problems I’ve seen them run into are basic algorithmic issues. “I want the ball to change direction when it reaches the wall” we’ll “perhaps we can let the ball test if it is at the wall? Here’s a block that does tests”