'Imagine Cup' Game assets

I was asked to create backgrounds and characters for a game that students were going to make for a competition. The game story was of an astronaut who crash lands on an alien planet, level one he is on the planet surface  Level two is an underground city on the planet where he has to find the parts to fix his ship. He ends up leaving on an alien ship in level three. 

 I took this opportunity to organised a few of my piers together and be the art director for the game. I created level one above and then asked my piers to create the other levels, sticking to my art style and after a few mock ups, these were the final level previews.