Numerical Analysis/Learning projects and learning resources

Since there is already a lot of material on this topic freely available, we will try to organize and supplement, rather than duplicate. In particular, here we collect exercises and quizzes, which would be inappropriate for Wikipedia. The topics are organized and ordered as in Wikipedia's List of numerical analysis topics. A topic is only listed here if we have something to add, such as a Wikibook link (prefaced with b:), a learning module here, further examples, exercises, quizzes, or links to external learning resources.