The Math Mammoth’s Skills Review Workbook complements the lessons in the Light Blue series Worktexts (sold separately) by providing additional practice for students throughout the school year. Each grade level’s consumable workbook offers 70 to 100 (depending on the grade) colorful one-page worksheets, giving students a spiral review of the concepts they’re learning. Worksheets are labeled by chapter number, so it’s easy for parents to choose which worksheets to use and when to assign them. Answer Key sold separately. 42 pages, softcover. Grade 4.