I am sorry that you are having such a bad experience. Most of my quilting is self-taught, but I did have a mother that taught me to sew and I took home-ec in jr. and sr. high school. I took a few quilt classes to see if there was information that I needed because I couldn't see why it was considered so difficult. When I was in the classes I honestly tried the techniques being taught to see if the instructor had some enlightening information. (One class was for hand quilting and the instructor asked me why I took the class, because I was interested in how she marked her quilt. I was really hoping to learn the best way to make a whole cloth quilt.) And I was given a class in paper piecing - that was enlightening to me, but I just found the pattern in my UFO box. My favorite kind of "class" is on-line, usually YouTube. The main reason I dislike going to classes is because some students are a royal pain. They constantly challenge the instructor and you want to tell them "I didn't pay for the class to learn your way, please let the instructor do her job."
So you are not alone, not all classes are a great experience.