Explore with hands-on learning with these replicas of dinosaurs or animal bones. Smooth bone pieces are weighted with inset steel Ignite children's passion for learning, and spark a desire for a deeper understanding of the world and history Integrate these into various subjects, such as science, history and language arts, as children learn about different types of dinosaurs, extinct animals or prehistoric times through books and educational materials Set includes 20 bones. Includes ten 3" long bones, five 4.5" long bones, and five 6" long bones For ages 2 years and up 2 years & up. Encourage experimentation and curiosity with an authentically inspired set of Big Bones. Exploration of big bones can be an engaging and educational experience for young children, sparking their curiosity about the natural world and fostering a deeper understanding of anatomy, history and science. Children can take this easy-to-clean, weighted set outside for exploration with messy materials like dirt, mud, or water, or use inside during loose parts activities. A variety of lengths encourages the discovery of size relationships, counting, and patterning.