Have you ever thought about the ways we, as chemistry teachers, talk about the concept of energy? Think about all the different terms we use when we talk about the role of energy in our curriculum: endothermic, exothermic, heat, specific heat, heat capacity, enthalpy, temperature, kinetic and potential – just to name a few. To further complicate matters, our physics and biology colleagues also talk about energy, and they bring their own set of terms and conditions to the conversation. Have you ever considered how the use of this disjointed vocabulary impacts how students think about energy?
One of my goals this year was to try and present a more accurate and consistent description of energy to my students, and to unify the definition between disciplines. I felt it was important for my students to understand that energy is energy. There are not different kinds of energy. The energy they learn about in biology is the same energy we talk about in chemistry and the same energy they study in physics. Students should not need to know three different definitions of energy for three different classes. I sat down with the teachers in my department and we drafted a definition of energy we each felt comfortable with using consistently in our classes. The definition we agreed on was, “energy is a conserved, substance-like quantity that can be transferred and has the ability to cause change”.
I challenge you to ask your students to define energy in their own words. Walk down the hall and ask students in a biology, physics, or earth science classroom to do the same. Do you think the definitions would be consistent?
The Modeling Curriculum does a nice job of providing analogies to students to help them understand the concepts of energy and energy transfer. Modelers use a tool called “energy bar charts” to help our students understand energy changes in a system. In my next article I will go into more detail on energy bar charts and how you can use them in your classroom.