The Campus Computer Store has Microsoft products at very low prices, so you might want to try Frontpage. Microsoft Word now has good HTML editing tools as well. I like a shareware Mac editor called Pagespinner that can be downloaded. Or, you can just use a simple text editor like simpletext on the Mac and wordpad on Windows. The HTML codes you need to write your class assignments are not very complex.
Content is more important than formatting.
The best thing to do is just get started, using whatever editing tool or program you have. Keep a collection of bookmarks to pages you like. In some ways this is the most difficult part. Many programs now do all three steps, but often it is necessary to use a program like Fetch on the Mac or WS-FTP on the PC to move files around. Learning some good habits from the start Read the Publishing Guidelines provided by TeamWeb.