Add a fun learning tool to your classroom with the Dowling Magnets Large Sentence Strips! Demonstrate sentence building, paragraph structure, grammar, punctuation, and other writing concepts on your magnetic whiteboard. Set includes 10 strips made of flexible magnet sheet, each measuring 24" x 3". Ruling measures 1.5 inches high and .75 inch high. Use with dry-erase markers only. Wait until the marker is completely dry before erasing to prevent smears. Child safety tested for ages 5+/grades K+. Constructive Playthings is committed to providing safe, compliant products and a healthy, safe working environment worldwide. Constructive Playthings fully complies with the CPSIA and works closely with our suppliers and third party, CPSC approved laboratories to ensure we meet regulatory requirements. We require that all products meet all applicable federal regulations, which we review on a continuous basis