Measuring can be a difficult concept to learn and to master. The ColoRule ruler uses color indication for an easy understanding of what each measurement mark represents. Common fractional marks at 1/8", 1/4", 1/2" and 1" have a designated color for quick recognition. The ruler features a key to help students remember which color corresponds to which fraction, and makes it easier to add the fractions together. 12" ruler features colored notches along the entire length of one edge. Has holes for storing in a 3-ring binder.