Great concept. Three stars, due to the fact that everytime you start, or are in the middle of, or are finishing a project there are ads. Basically, everytime you click/touch the screen. These types are games are great for my special needs son...there are just way too many ads. Since each project is so short...how about an ad after every two projects? That way the developers make money, but the player wouldn't be so aggravated...Just a thought. Plus, user less likely to uninstall=more $.