I've only taken the free classes.
Pretty much anything you can learn in a paid advanced class, you can learn in books.
I disagree with Asdea that you should never pay for a class on the Craft. The general notion, spawning from many Traditions' bylaws and regulations, is that you should never pay for *training* into a system. However, that pertains only to those Traditions who uphold this notion.. There may very well be systems of Witchcraft which charge even for training. That doesn't make anything wrong, unethical or lesser.
That being said, I have noticed that most of the so-called "magical schools" are frauds.. Or at the very least, nothing you can't find on your own through study and practice. I was subscribed to Magicka School a looooong time ago (and I should really go and unsubscribe because I am still being sent all kinds of spam from there) and it was nothing special. 90% of what they mentioned is covered way better in basic 101 books.
I could understand a Tradition needing you to pay for your own supplies or to chip into paying for the group supplies while you are training with them, like paying a dollar to help out with buying candles when you are learning about candle magic, but the whole "give me five dollars and I'll teach you how to cast a circle" kind of payment just seems lazy and a complete rip off to me since you can go to a local library, or even "google books" and find information on how to do it yourself. Granted, you may not learn how to cast a circle in that specific way, but if you aren't interested in that specific circle casting, then save your five dollars and buy a Subway sub.
For me, outside of a specific Tradition where you do need to go through their training, I have never seen an actual BTW (or other TIW) magical school online that was legit. I don't know how you can get the specifics of their program through a computer screen, and I can only think that most of the other material would not be "blog post" appropriate or friendly. That and I totally see $RW getting her disturbed paws all over it and re-writing her book for the oh...30th time with this "new and totally hip Wicca material" in it, so yeah, let's not have that happen.
I say crack open a few books (I'm sure you have already) and ask questions around here some more, it never hurts to get the right information from such an educated crowd.
It is my belief that unless you're learning about religion in a very removed, strictly scholarly way a school setting is no place to learn about spirituality. I used to get into this argument all the time with fellow Ojibwe natives at the school we attended. They taught Ojibwe language classes, and for a lot of people the language is a deeply spiritual thing (or can be). My friends were frustrated with the limited amount of spirituality mixed in with the language teaching...but they needed to be reminded they were learning Ojibwe language at a private catholic college!
To my mind, spirituality is much more organic, less structured than one teacher with a classroom full of students assigning general teachings and assignments. The closest religions I know that resemble that format have a church involved.
Online schools for religion seem more accessible and easier than doing your own research and finding your own teacher. I know it can be frustrating to wait sometimes years to find the right person to help lead you down your path...or to even define what your path truly is. But in my way of thinking, that's the best way to do it. Through growth, not a fake internet diploma.