3 years & up. Keep up with the time using this brightly colored Large Minute Sand Timer for Classroom Activities Indoors and Outdoors. This classic hourglass timer is the perfect tool to help children visualize time. Use this exciting timer for science experiments, time management, and other timed games. This sand timer is time-tested and made of durable plastic. Timer comes with matching colored sand inside of a glass hourglass. Available separately or purchase the whole set of 4. Measures 3.25"L x 6.375"W.