My first grader son's teacher is using this book daily. Now I know where she gets her tools that is why I got this book for my son to study him in advance at home. His teacher doesn't explain thoroughly in the class of what they are learning and my son's Daily Math Booklet as I always check he always gets lots of errors. I asked my boy why he has a lot of mistakes. He said that his teacher doesn't explain to them very well and she is always in the computer. Usually, kids don't lie but I would definitely address this problem to her during the Parent and teacher conference meeting. Sometimes, having a Ph. D. teacher is not good because they think the kids brain its just like them but forsake its a first grade. So hopefully, my boy would be ahead of the game once he will studying this book at home.