1. Suppose you were an elementary school teacher. If there were a long, straight sidewalk in front of your school, how could you use it to teach third-graders about the addition of positive and negative numbers on the number line? Invent a game to do this.
2. ╥Subtracting a negative number has a positive effect.╙ For example,#3 - (-2) = 3 + 2 = 5. How would you explain this principle to a student, by using money as an example? How could you use the idea of a ╥debt╙ in your explanation?
3. What is the difference between ╥-╙ (the subtraction operation) and ╥-╙ (a negative sign)?
