This is an activity students complete after they conduct a controlled experiment using food coloring and different temperatures of water. They drop blue and yellow food coloring into both hot and cold water, then record the amount of time it takes each cup to turn green (indicating mixing). Since students do not mix the food coloring themselves, they can conclude that the molecules in water are moving faster in the hot water than in the cold. This is a crucial piece of evidence for the effect of temperature on molecule motion that promotes that idea for the remainder of the unit. We make these posters to provide a visual summary reminder of this important experiment on the wall for students to refer to as needed.