Difficult pupils are best!

I have recently discussed music education with a friend who teaches organ. He had some very inspiring thoughts and ideas. One of them was: "The most difficult pupils make me develop most as a teacher." If your pupil doesn't progress successfully, you really have to work hard to improve your teaching methods, to break down the process into smallest and simplest steps that anyone can do. 
So - don't be discouraged if you have problems at your classes - it is just a step towards being a better teacher.