If you haven't checked out Roblox, do your self a solid and give it a go. Then try Roblox Studio, the IDE used to visually create games. I've been having real fun using Roblox Studio with my 8-yo niece to try out game ideas she has had. Having created a couple of these "games" - more like playing around with built-in assets - I'm convinced Roblox does for kids what Basic did for a lot of middle-aged nerds when they were kids themselves.