Lynda.com offers lots of the beginner WordPress classes that are free of charge. Their learning format breaks training into smaller, digestible chunks to allow you to learn everything at your own pace. (Alternatively, you can also skip what you know and pick up a few classes on subjects you want to learn more about.)
There are many beginner classes that are free, and their monthly charge is pretty affordable if you want it all!
Also of note: Many of their training classes are now Closed Captioned for people who are hearing impaired or are otherwise unable to listen to the video. (Great for jedi-ninja-cubicle learning!)
The linked page should go to a WordPress search page on their site, but don't let that constrain you. If you have learning to do on many software or programming subjects, check out Lynda.com - you won't be disappointed.