During the thermal systems section of chapter one, I do a demonstration to show students how much energy is contained in a small number of kilocalories. I light an almond on fire and we time how long it takes it to burn. As it burns, we discuss how the energy is released into the human body after eating an almond or any type of food, and why the body’s temperature doesn’t rise to the extent of the burning almond. From there we go on to discuss other foods that may provide a large amount of energy and why.