This is an activity (located on page 3 of the PDF) about the mixture of materials in bone and how they affect its strength. Learners will play the part of nanoscientists looking for new ways to repair broken bones. Learners will experiment with sponges and Plaster of Paris to find the best mixture that makes the strongest bone. This activity also serves as an excellent model of how nanoscientists must test and retest their formulations to create a desired result. Relates to linked video, DragonflyTV Nano: Bone Regrowth.