I define a class site as a repository for all the information you present to your students in class, information in addition to what you've taught, and things they may find *cool* to tie in to their learning. However because web page design started off as a very techy thing many people are still hesitant to put their classroom information online. I'm here to tell you Google Sites is the answer to their prayers.
Google Sites is very wysiwyg*, just like typing a document in Microsoft Office and saving as a web page, but you're typing directly into a web page. Depending on your computer comfort level you could sign up for a Google account and play your way through setting up a site or read basic information about Google Sites or tutorials on making a Google Site before venturing forth.
The easiest way to start using Google Sites is to create one (1) Web Page and just type your information in. Use the Insert menu to add interesting options to your pages (a photo, a class calendar, maybe). When you're ready to explore even further, read about the types of Pages you can create and add to your site.
By masking the coding and limiting page options to the most useful any teacher can create a great looking web site for their class.
*wysiwyg: what you see is what you get