Scratch (Scratch.mit.edu) is a computing tool that helps students think creatively, reason systematically, and work collaboratively. As a drag and drop “block” coding language, Scratch is easy to learn for people of all ages. Scratch Jr., for younger students, is available for iPads.
Code.org/Hour of Code (code.org/learn) offers many one-hour tutorials that teach elements of coding to all ages. They also offer online, self-guided “courses” for students from beginning readers to more advanced, at studio.code.org.
codeSpark (codespark.org) created The Foos (thefoos.com), a word-free computer science learning game for kids as young as 5. The free app is available for ios, android and kindle, and there’s a desktop version as well.
Tynker (tynker.com) has guided, self-paced courses that let kids earn badges as they master different programming skills. Tynker courses are for mostly for sale, but there are a few free classes, too.