Surface Area - After discovering that ordinary flour dust can be explosive, Lara and Anushua explore the importance of surface to area to volume ratio at the Science Museum of Minnesota. They conduct soda explosion experiments in the museum's Big Back Yard, investigating how surface area affects reactions. Finally, they visit the University of Minnesota where they learn how scientists are developing more affordable solar cells with nanotechnology that increases the cells' surface area. Stained Glass - Alettie and Yvonne visit the Glass Experience exhibit at the Museum of Science and Industry in Chicago and learn that nanoparticles are responsible for the colors in some medieval stained glass. The girls are surprised to learn that nanogold makes glass red! They go to Northwestern University to explore the relationship between size and color of nanoparticles. They create different sizes of gold and silver nanoparticles to produce a variety of colors, which they use to make their own works of art.