I'll be using Lucidity in class to receive and display your anonymous questions in order to guage which topics students find confusing. Here's the really cool part: it's built using only the tools you will learn in this class! I encourage you to look at the source code on my GitHub.
An extremely thorough source of documentation on HTML, CSS, and many other web-based technologies (including MathML and browser graphics). Somewhat technically inclined, but you can find tutorials here as well.
Designed to teach beginners interactively, Codecademy has become a crowd favorite among tech startups in the country. I've tried it before and found it to be an excellent option for those who have no prior programming experience.
w3Schools provides something akin to a quick lookup guide for languages found on the web. They do offer tutorials, but these rarely go into any detail. Some feel that w3Schools is inaccurate or teaches bad practices (see w3fools.com). I recommend using w3Schools in cases where you only need a refresher on material you've learned before.
This O'Reilly manual, written by Douglas Crockford, teaches only those parts of Javascript which the author believes are worth using. Regardless of whether or not you agree with the author, he does a good job presenting a particular subset of Javascript. At only 170 pages, the book is a quick read as well.