Remeber though, that in math it is very important to show the work. It might look extremely stupid at this level, but I would still insist she does it how the teacher asks her to do it. Maybe she would feel better if she got some validation from the teacher, that her way of thinking is good but that there is also another way she needs to master.
My DS, taking classes from Art of Problemsolving, is also mad at the fact that he has to "show his work", but those people really know why they are making them do that. Even if it is more time consuming.
