These giant magnetic geoboards remove the need for teachers to fuss with elastics to display what students are working on. Simply use a dry-erase marker to connect the dots. Designs match the common geoboard set ups: 5 x 5 pin, 12 pin circular, and 24 pin circular are 11" x 11" (28 cm x 28 cm) size, and 11 x 11 pin and isometric are 17" x 17" (43.2 cm x 43.2 cm) size. 5 pieces. Grades K+