Using number lines

October 18, 2006
Today in our pre-algebra class we practiced using number lines to add and subtract positive and negative integers. We pretended the number line was a road and if our integer was positive we walked ahead, but if it was negative we had to walk backwards. The trick think was if we were subtracting....then we had to turn our hiker around. It was fun! So if you want to subtract a negative, you turn around and face the negative direction and walk backwards, which is the same thing as walking in the positive direction. For some of the students, this was a better way to see what was happening in their equations.