During my AFX in the fall of 2024, I created a Unit Plan for the Grade 7 Science topic on Heat and Temperature. As part of this unit, students conducted an experiment in groups to build their own thermometers, allowing them to directly observe the expansion and contraction of liquids and gases.

Initially, students marked the liquid level at room temperature. After adding heat, they noted the new level indicating expansion. Next, the thermometers were placed in a refrigerator, and students observed the liquid contracting due to cooling. Finally, the thermometers were left overnight to gradually return to room temperature.

The following day, students noticed that the liquid levels had risen above the original room temperature mark. This prompted a discussion about potential causes. One hypothesis was that the current room temperature was higher than at the start of the previous day.

Additionally, students observed that thermometers containing more air had higher liquid levels in their measurement columns. This indicated that air, being a gas, expands more significantly than liquid, pushing the liquid higher. The experiment effectively demonstrated two expansions occurring simultaneously: the expansion of the liquid itself and the greater expansion of the gas.

This observation directly supported textbook concepts and provided an excellent opportunity to integrate hands-on experimentation with theoretical learning. Including a photo of this result in my teaching slides helped students clearly connect their practical experience to the course material.