3 years & up. Include sensory elements to learning the alphabet and counting with the engaging ABC & Numbers Sound Puzzles for Practicing Literacy and Counting. Children are sure to be captivated by the whimsical patterns under each puzzle piece. The light activated sensors trigger songs and sounds. These sensory features are an engaging way to reinforce early learning concepts. For extra learning, encourage children to identify the color of the letters or numbers they place. Each self correcting puzzle requires 3 AAA batteries each, not included.