In this activity, students experiment and observe the similarities and differences between human-made objects and nature in small groups. Students compare the function and structure of hollow bones with drinking straws, bird beaks and tool pliers, and bat wings and airplane wings. A classroom discussion can be held to discuss similarities and differences that are observed along with follow-up assessment activities such as journal writing and Venn diagrams. This activity requires a 60- minute time period for completion. (Author/SOE)