This is a great learning toy with a 96 card activity deck designed in co-operation with Highreach Learning, Inc. The deck was created by a teacher. It has lessons on three difficulty levels and the wide variety of unlabeled blocks encourages children to compare blocks physically, not just visually. These simple materials allow children to grasp all mathematical principals up to the level of algebra. Children can play with them like ordinary blocks, and thus are engaged instead of threatened. Children stack the blocks next to other objects imitating Greek and Egyptian methods of measurement, and achieve a tactile understanding of the metric system. Arithmetic principles are firmly established by hands on work and observation. A valuable tool for children from 3 to 14 years old. Set includes a beautiful log ruler and stand and 66 Tree Blocks 24-1cm, 12-2cm, 8-3cm, 6-4cm, 5-5cm, 4-6cm, 3-8cm, 2-10cm and 2-12cm. Special dice. Cotton twill sack and our new activity deck.