Hugh explained that forensic scientists test chemical residues to tell if the people should be convicted. He asked the class a question about how one could find a person who started a fire in an arson case. Hugh taught about the tools forensic chemists use, especially using the electromagnetic spectrum to measure a molecule's vibrations. Vibrations have many different forms: wagging, stretching, and scissoring are examples. Different bonds absorb different wavelengths because of the vibrations that bond makes, so a forensic chemist can identify the type, if not the exact identity, of an unknown chemical.

Next the students looked at a specific model on MacSpartan. Hugh ran a frequency calculation and found out that water has three different ways it can vibrate. The students studied a hypothetical case of five suspects who each chemical found on his hands. By studying the results of a spectrometer, they found the types of light each chemical absorbed, and therefore which chemical was the one used in the crime.

After morning break, Cornelia began teaching about trash archaeology and its use in investigative science. Trash archaeologists search trash to find out more about the suspect. The students received two bags of trash and tried to find clues to identify the owner of the trash. (The trash was non toxic and did not contain any harmful objects) After studying the trash, the students questioned "suspects" with yes or no questions. After deciding whose bag it was, students made presentations about how they arrived at their conclusions.