Detailed Description This set of 3 instructional rulers is designed to simplify teaching and learning measurement. Created for autistic students, this Ruler uses a visual model to simplify measurement. All inch increments are in black, while the 1/2 inch increments appear in red on the first ruler. The second ruler then adds 1/4 inch increments in blue, while the third one adds 1/8 inch lines in green. Measurement becomes as easy as counting the colored lines!