Amazon.com : SCRIBBLEDO Dry Erase Graph Whiteboard 9" x 12" Double Sided Dry Erase Board with Grid for Home, School, Classroom, Kids and Students Portable Grid Board for Graphing and Geometry :
Amazon.com : Magnetic Dry Erase Graph X-Y Coordinate Grid Whiteboard Sheet with Improved CleanWipe Surface by AgilePacks 19" x 19" for Classrooms, Math, Graphing Plus Magnetic Cleaning Cloth : Office Products