If you haven't yet listened to one of Grammar Girl's audio podcasts, give these lessons a try! Her grammar lessons are fun and relevant, often including interesting references to stuff happening in our culture today. Each lesson also includes a transcript, and audio files are available for download, so you can listen to them on your iPod.

Rollin', Rollin', Colon

Semicolons

Separate pages—whole pages—on the semi-colon, the colon, the dash, the comma, and the apostrophe.  Clear instruction.  Very informative University of Florida, St. Petersburg, site.  Note: the links to the separate pages are kind of inconspicuous at the bottom of the page.

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Good coverage of the rules, but the most useful part of the site is the interactive quiz.  Students decide whether a sentence takes a colon or a semicolon.  Correct answers and explanations are provided.

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