Rub a chalk-dust filled eraser over this durable chart and leave the pattern on the chalkboard. Filling the entire board with the desired pattern enables a number of students to do board work at the same time. Chart measures 36” x 42”, attached to sturdy spring rollers, on durable backboard equipped with chain hangers to allow chart to be easily pushed against board. Pattern consists of 11/2” squares. Dots divide sides into 5 parts of decimals or fractions.