3 years & up. Develop phonemic awareness and vocabulary with this set of 16 visually appealing rhyming pebbles. The colorful illustrations provide children with a fun way to learn sounds and phonics. Durable stones provide a fantastic tactile way for children to learn as they sort and match eight rhyming pairs. Pairs address the following sound families, -ag, -an, -ap, -at, -ing, -og, -ot and -ug. Stones measure 2".