Occupy busy hands and improve focus, attention and concentration with these smooth sensory stones, designed to calm and still body and mind in a non-distracting way. With three different designs to choose from, a child can select the stone that they think they will find most helpful. The discreet natural colors and tactile nature invite sensory interaction. Each set includes twelve stones; four each of three designs (heart, knobbly and hollowed). Size 2.5-3". Age 3+. Recommended age 3+ years