This lesson comes from the Math Assessment Project (MAP) and is intended “to help you assess how well students are able to understand and use directed numbers in context. It is intended to help identify and aid students who have difficulties in ordering, comparing, adding, and subtracting positive and negative integers. Particular attention is paid to the use of negative numbers on number lines to explore the structures:

• Starting temperature + Change in temperature = Final temperature
• Final temperature – Change in temperature = Starting temperature
• Final temperature – Starting temperature = Change in temperature”

Like all MAP lessons. this includes an assessment activity to do first, with a rubric to support teachers giving feedback to students. Then for the activity at the heart of this lesson, students are working in groups.