Description: One of a series of documents describing the progression of a topic across several grade levels, informed both by research on children's development and by the structure of mathematics. Grade 5 students learn and use such conversions in solving multi-step, real world problems (see example in the margin). Students learn about a unit of volume, such as a cube with a side length of 1 unit, called a unit cube. In Grade 6, students build on their understanding of length, area, and volume measurement, learning to how to compute areas of right triangles and other special figures and volumes of right rectangular prisms that do not have measurements given in whole numbers. In Grade 8, they use their understanding of volume in learning and using formulas for the volumes of cones, cylinders, and spheres. Connection to the Number System.