Laurie Rogers:
It’s simple to teach mathematical positives and negatives to a child. It’s been done successfully with the number line around the world, in private schools, homes, tutoring businesses and online. Unfortunately, many schools in America no longer teach the number line, don’t teach it to mastery, or they cloud any fledgling understanding of it by emphasizing other, less-effective methods.
First, I’ll explain the number line. Then I’ll show you what’s being emphasized in its place.
Traditional Math Method Used to Teach Negatives
The Number Line
A number line is a straight line with numbers listed at intervals. Typically, “zero” is a point in the middle, negative numbers are listed to the left of zero, and positive numbers are listed to the right of zero. Arrowheads are placed at each end to show that the line and numbers continue to infinity. Each point is assumed to correspond to a real number, and each real number corresponds to a point. Like this: