Children will have fun with this construction and early learning manipulative. Ideal for developing fine motor skills, and for counting, sorting and creative design. How many pebbles can you stack before they topple over? Encourage visual perception, fine motor skills, sorting, counting, stacking, and more. The wonderful tactile experience of the smooth, rubbery pebbles in six different colors will delight the senses. Set includes 36 plastic pebbles in 6 sizes (0.75" x 1.125" x 0.25" to 2.25" x 3.25" x 0.25" ) and 6 colors, and 20 double-sided full-color activity cards packaged in a sturdy plastic storage container.