This Problem Set is a part of the Lesson 4, Unit 5, Grade 3. In this lesson, students work at stations to represent a given fractional unit using a variety of materials. (For example, students at the "fourths" station create fourths from a length of string, different-sized pieces of paper, a beaker of water, and a ball of modeling clay.) Then they do a museum walk and consider the relationships of the various models and the relative sizes of the fractional units presented.