http://www.w3.org -- The World Wide Web Consortium (W3C) develops specifications, guidelines, software, and tools for the Web. The primo resource for information and tutorials.
http://www.w3schools.com -- W3Schools has free web-building tutorials.
http://www.actden.com/fp -- Good resource for introducing FrontPage in the classroom.
http://www.angelfire.com/super/badwebs -- The World's Worst Website.
http://www.htmlcodetutorial.com -- HTML Code Tutorial.
http://javascript.internet.com -- The JavaScript Source.