Affordable Learning Solutions: Open Educational Resources by College

"This course is comprised of a range of different free, online materials. It is based on The Global Text Project: Sue Conger’s text The New Software Engineering."

MIT course taught in 2010. "This class is a hands-on, project-based introduction to building scalable and high-performance software systems. Topics include performance analysis, algorithmic techniques for high performance, instruction-level optimizations, cache and memory hierarchy optimization, parallel programming, and building scalable distributed systems."

Interactive courses on JavaScript, HTML/CSS, PHP, Python, Ruby, APIs created by members of the community.

Instead of pulling problems out of a database, Wolfram Problem Generator makes them on the fly, so you can have new practice problems and worksheets each time. Each practice session provides new challenges.

Khan Academy provides video lectures and accompanying practice problems in topics like differential equations, linear algebra, etc..

MIT OpenCourseWare (OCW) provides course materials for a wide variety of math subjects. Assets vary by course, but many courses provide practice problems and solutions.