My ds6 in kindergarten has had this problem. I think some teachers want a child to do "A", then "B", then "C". Yet, the child is so far beyond, he/ she can't perform a,b,c as the teacher asks. I decided to stop doing those easy readers with my ds because he starting fighting me every time I tried. I did try to explain this to his teacher and ask if she could try something harder with him. There was a small compromise, but basically we're seeking outside guidance and hoping we can hang in there to the end of the year.