Number Pebbles Sum Building

These durable and tactile pebbles can be used in sand and water both inside and outdoors. Each pebble is cast from a special stone and resin mix and engraved and handpainted with a numeral. Contains 50 Pebbles - contains two of numbers 0-20, two of operations +, - and =, one of operations x and ÷. Ages 3 and up.