In Codecademy, older kids and teens write computer code. They set their own pace through lessons on every major modern programming language, including PHP, Javascript, Python, Ruby, HTML, and CSS.
"Coder is a free, open source project that turns a Raspberry Pi into a simple platform that educators and parents can use to teach the basics of building for the web. New coders can craft small projects in HTML, CSS, and Javascript, right from the web browser."