I found something easy to play with on iTunes U. Geometry with Swift Playgrounds - Free Course by Apple Distinguished Educators on iTunes U It's a Logo like approach to programing. I haven't bothered with the course itself, but in the resource page there's a playground that you can download and use. It stands alone pretty well. This is easier than Apple's second lesson book, and way easier the Project Euler. All you need is some basic geometry, and what you don't know you can probably pick up along the way. Note. Trying to install the playground directly from iTunes U did not work. I had to open it in GoodReader and unzip the folder, then open into Playgrounds from there. I'll be exploring iTunes U for more stuff. I should have thought to look there earlier.