In this Energy and Environment activity (page 9 of the PDF), learners calculate the mass of a piece of gum, compare it to the mass of the gum's packaging, and then create a bar graph of the results. They explore how packaging can account for a significant amount of a product's mass and price, and learn the importance of reducing packaging. Although this was designed to be a pre-visit activity for a workshop about garbage and recycling, it also makes an excellent stand-alone activity.