According to your answer, it looks like you could use some help with borrowing in a subtraction problem. We recommend starting with Volume 1 of the Learn Math Fast System. You'll learn how and WHY we borrow in a subtraction problem.
RESULTS: 2nd Grade Level, however, the Learn Math Fast System is for all ages. Volume 1 covers all math facts to build a solid foundation in math. There is no mention of grade level within the books.