Frustrated!!!

The children seem to like the new Internet Academy program but I am starting to get frustrated.
The other day Seri did a chapter on the Olmec's. I came to check her test and she had not passed, getting nearly half of the questions wrong. She asked to take it again stating that she was confident she knew the material. Once again she bombed. In sheer frustration I made her sit with me and go back through every lesson. Now the lessons are presented just like pages in a book that she has to read through. We drew maps, I constantly asked her repitious questions, we looked up things we didn't know but were curious about and generally did everything I could think of to make it sink into her brain. So after two hours she took the test again and did not miss a single question.
So why did she have such trouble the first two times? I think I have narrowed it down to a few reasons. First, she was in a hurry to "get through it". The material was just another obstacle for her to pass in her quest to stay on time with her assignments. There was no incentive to actually know the material, just to pass the test and move on, not to remember any of it beyond the day. Secondly, she could care less about the Olmecs and thus had no desire to truly learn it just because someone told her to. Besides, what is she going to do with her very limited knowledge of the Olmec people?
Somewhere along the line, love of learning for the sake of satisfying curiosity has been rejected for the sake of "well roundness". Let's make you a well-rounded person who knows a lot of crud about everything, but nothing significant about anything. The all to familiar "Jack of all trades, Master of none".
I truly regret that I did not homeschool from the beginning. That my children were exposed to these traditions of force-fed education. That passing a test means more than having learned, really learned- not reguritate, something new. Seri is in such a hurry....... she doesn't even grasp the true meaning of everything she reads. She now has this uncanny ability to memorize things she thinks will be on a test without really knowing anything. How is this OK? No wonder half the children the schools are producing really know nothing.
Michael on the other hand truly tries to learn but is so afraid of failing. Every time he answers a question, even if he knows it, he does it hesitantly, trying to see in your face any kind of sign that he is going to get it right. Such a response to the fear he felt during the short time we had him in PS.
It is amazing how much I am having to "de-school" my children. Finding ways to bring back their curiosity, question why about everything, become passionate about a subject or two, find joy in solving problems and peace and securtiy as they grow up way too fast.
So in spite of all of this, why can I not let go of some "formal" education. I have this fear that keeps me tied to some sort of resembalance of Public education even though what I really want to do is break free completely and bunk the system all together. Is it my fear of failing and society telling me "I told you so?". Is it my lack of trust in God when he reasures me according to my constant praying that this is what he desires for my family?