## Making sense of things through numbers

Teaching Guidance for 11-14

#### Energy calculations tell us what can happen

**Wrong Track: **Energy makes things happen.

**Right Lines: ** Energy calculations tell us which processes are possible and which are not.

#### Energy is not a physical quantity

**Thinking about the teaching**

Energy is not some physical property that makes things happen. Rather, it is an interesting quantity, calculated in many different ways, that tells us whether or not particular processes are possible. The amount of energy available in a particular situation limits what is possible. Actually doing the calculations, finding out how much energy is available, comes later, in episode 04.

In this introductory phase, you might find that it is useful to draw an analogy with having a certain amount of cash. The quantity that you have limits what you can do, but does not compel you to do anything. Most importantly, it tells you what is not possible.

Keep it simple, allowing cash transactions only!