Learning goals: Teacher Facing Determine the final temperature given the starting temperature and the change in temperature, and explain (orally and using other representations) the solution method. Explain (orally) how to create a number line diagram that represents adding signed numbers. Write an addition equation to represent a situation involving a temperature increase or decrease. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 7.5 Rational Number Arithmetic, Grade 7.