Ms. Bell has been busy again finding ways to make thinking visible?. She installed a clothesline, stretching across the front of her whiteboard wall. The mathematicians are working on estimating and testing their answers to problems. After students work on their problems, they write their estimates on the "answer clip." Then they place their answer on the clothesline. Ms. Bell will mark the high and low with a red tag. As they evaluate their answer and where it falls on the clothesline, the students learn relative values and how to use relative values to assess their answers to problems. Pure genius, Ms. Bell!