
This simple experiment can be used as a way to introduce or reinforce the scientific method. Students design an experiment to test which materials are the best insulators by measuring heat loss.
The materials are simple, and the experiment doesn’t take very long. You just need two jars per group, a thermometer, hot water, and a variety of insulation materials, such as cotton, newspaper, styrofoam, cardboard.
The first page allows students to design the experiment and discuss what type of data they will need to gather. The next page provides more detailed instructions on how to set up the experiment. A beaker or jar is filled with hot water; I use a kettle to heat up water in my classroom. A thermometer measures heat loss over 14 minutes. This is compared to another jar that has material wrapped around it for insulation.
Students answer questions about the set-up, identifying the control, dependent, and independent variables. They gather data and create a graph that shows how temperature changes over time. Students should be able to see from the graph that the beaker with insulation changes temperature more slowly than the one without insulation. Instructors then compile all the group data so they can compare different materials and determine which one is the best insulator.
The graph shown below is a example of the type of graph that students will create based on their data. You can opt to run the experiment longer than 14 minutes which may have more dramatic results. The time is based on my class period which is about 50 minutes, leaving time for discussion and completing the worksheet.

Worksheet ends with a CER (Claim, Evidence, Reasoning) that answers the question about which materials are the best insulators, or which ones result in the slowest loss of heat.
There are two versions of this worksheet, a regular version with mostly open-ended questions, and a “bee” version that has easier questions that are multiple choice. The bee version also has the graph set up (X and Y axes labeled). Bee versions are created for differentiation in classes that may have ELL students or students with special needs.
Download PDF Google Doc Key (TpT)