While it does provide problems for my 3rd grader to practice, so far it appears there is only 1 set of problems per section. Since we have only gone through 3 of the sections, I hold out hope that there are other sections that do not have the same 25 problems in the same order...if it does, I would rate this a 1 star. Further, though it said ages 9 - 11, it appeared far to easy for my 9 year old to solve. Pay a few bucks more for something that hopefully gives a little more variety and randomness.