E=mc² Energy Ledger
Introduction:
Einstein’s most famous equation, E=mc², says energy (E) and mass (m) are connected. The “c” is the speed of light, and it is enormous. Squaring it makes it even larger. That means a very small amount of mass can represent a huge amount of energy.
This activity uses an “energy ledger” to help students think about how energy shows up in everyday life, and why Einstein’s equation shocked the world.
What You Will Need:
Paper and pencil
A list of everyday energy examples (light bulb, phone battery, food calories, car gasoline)
Optional: access to simple energy facts (from a book glossary or teacher-provided sheet)
Step-by-Step Instructions:
Make two columns on paper: “Energy Example” and “Where the Energy Comes From.”
Write 5 everyday examples, such as:
A light bulb glowing
A phone charging
A person running
A car driving
A microwave heating food
For each example, write what is being changed: chemical to motion, electricity to light, and so on.
Now write one sentence: “If mass and energy are connected, then energy changes are also connected to matter.”
Discuss: In what situations might mass actually change into energy? (Answer: extreme physics, stars, nuclear reactions.)
End by writing a kid-friendly definition of E=mc² in your own words.
What to Look For:
How many ways does energy change form in daily life?
Why is the speed of light in the equation?
What makes Einstein’s equation feel surprising?
Fun Fact:
The Sun shines because of nuclear reactions in its core. Tiny amounts of mass convert into energy, and that energy travels across space as sunlight.
Safety Tip:
If you discuss nuclear energy, remind students that this activity is conceptual and classroom-safe, no experiments involve radiation or hazardous materials.
Journaling Prompt:
Write a short reflection: “One place I see energy every day is…” Then explain what form it starts as and what form it becomes.