Pre-printed lines offer a great work place to practice penmanship, sentence writing and more. Durable lap boards are 9" x 12" and can be used with all dry erase markers. An environment friendly way to learn, as you just write, wipe off and re-use with no waste. Comes with eraser and marker. Marker is non-toxic and conforms to ASTM D4236. Each set includes 12 boards, each with a marker with eraser.