Superoll by Dan
Dan was six when he made this rolling ball game. It is built in Unity, with game design, art and level design by him.
Since 2012, we have used each summer to work on a game together. I handle the programming duties (though I hope in a couple of years he'll be able to do more of that too), but I help him design the game and build as much as he possibly can.
In 2012, he designed a great little platform game called Cave Saver. We made a video of him playing and explaining the game.
In 2013, he wanted to do a 3D game, and I wanted him to start using modelling tools, so we settled on a design based around Super Monkey Ball - one of his favourite games. I blogged some of the process at our game summer blog. As in 2012, we ran out of time over the summer, so have been completing it in spare weekends here and there.
It is now finished, and can be found here. The aim is to reach the black obelisk goals as fast as possible, collecting as many coins as possible, to score highly. Red door gems open doors, green gems give you boost.
I wrote the code (there's not much), it uses the Unity game engine, and Dan did the level design, designed the game, and chose the textures and sounds.
The most interesting thing about Dan's design (and it was his idea, totally) is the fact that there is one large level, but many different routes and goals within it. Figuring out which set of coin to collect and which door to go through adds an interesting set of choices to the game. I think there's a lot that could be done with this. I'm rather itching to have a play with the idea, but it's Dan's game, so here it is, as he made it.