Assalamu alaykum wa rahmatuLlah,
First, with regards to contemplating divorce, Umar bin Khattab was once told by a man that he wanted to divorce his wife. Umar asked why, and the man said because he was no longer in love with her. Umar told him that family ties are not built only on love, for if they were, then no marriage would continue!
Please don't divorce your wife for this reason, especially if she is good to you, and strives to be obedient to you and Allah. There are many many who are worse... this is but a small trial in the grand scheme of things.
You have to bear in mind, it's difficult to teach and old dog new tricks, and you can't resent her for her upbringing. You had the choice at the time of marriage, and now she has two of your children. Is it her fault that you've now changed your mind?
My recommendation would be to not send her off for classes, etc, but rather try and find something you both like doing together. This isn't her problem, she's happy with you! This is *your* problem, you need to put the time in to resolve it. There is no quick fix. Rather than make her read books, take her to events. I'm not sure whereabouts in the world you're from, but I'm sure there are a lot of Islamic events and conferences within a reasonable travelling distance. Not only that, there is a lot of media you can watch together (e.g. "Occupation 101", and "Peace, Propaganda and the Promised Land" if you want to learn about the Middle East crisis).
You need to slowly expand her mind to other things, and raise other topics of conversation with her (and she needs to put the effort in to pay attention too!)
Also, be careful with her friends... if they're not interested, they'll drag her away. Try and encourage her to be with people who are more like how you want her to be. I'm not sure how you'd do that because I don't know your situation, but insha'Allah you might get some ideas.
But please... please... please... do not divorce her! You have absolutely no idea what it'll do to her, what it'll do to you, and more importantly, how it will affect your children! You're the man, be a man... deal with it! Treat her with kindness and guide her, and just be thankful that she is good to you. There are many many women out there who openly abuse their husbands and have trials greater than yours.
And fear Allah most of all.
Assalamu alaykum wa rahmatuLlah