The Cuisenaire rods fractions kit is used for mathematical study, and has 12 trays of 74 rods for strengthening student understanding of fractions, including equivalent fractions, addition and subtraction of fractions, ratios, and the concept of finding "families" for unlike ...The Cuisenaire rods fractions kit is used for mathematical study, and has 12 trays of 74 rods for strengthening student understanding of fractions, including equivalent fractions, addition and subtraction of fractions, ratios, and the concept of finding "families" for unlike fractions. The kit has self-checking activities for developing students’- computational skills, with a set of overhead rods, and a 64-page book, “-Everything’-s Coming Up Fractions with Cuisenaire Rods,”- for instructional use. The set is made of wood for durability, and is suitable for grades 4 to 6.