Support your students early math skills with the Classroom Number Line. Each number line bulletin board set includes 12 pieces (22" x 6.5" each) that feature numbers from -20 to 100. The number line measures 22' long when fully assembled and is divided into sections in multiples of 10. Color-coded for even and odd numbers, this math resource features a convenient write-on/wipe-away surface, as well as a helpful resource guide.