This problem book comprehensively covers six years of elementary school math and aligns with the 2020 curriculum guidelines. - Title: Problem Book for Thorough Understanding of Elementary School Math in One Book - Publisher: Kanki Publishing - ISBN: 9784761268672 - Target Grade Level: Elementary School - Contents: Math problem book - Features: Compliant with the 2020 curriculum guidelines Thank you for viewing. I purchased this new on Amazon and have never used it. Therefore, I am listing it as new and unused. Please refrain from purchasing if you are sensitive to items stored by a non-professional. There are no folds or writings. *I am a non-smoker and do not have any pets. Please feel free to ask any questions in the comments section (^^) Thank you for your consideration.