Mixed addition and subtraction within 20 color by code number GROWING BUNDLE coloring practice pages are a fun way for your first grade or 2nd grade students to practice their math facts up to 20. These mixed addition and subtraction to 20 color by number worksheets make an easy, no prep, colorful bulletin board display, too! Choose the coloring pages you want to use, print them, and have students complete them with colored pencils, crayons, or thin markers. Your students will love these desig