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How Can Students in Grades 3-5 Understand Energy? A Learning Progression Approach to Understanding a Core Idea in Science

Presenters • Sara Lacy • Sally Crissman

TERC, Cambridge TERC, Cambridge

Collaborators: • Marianne Wiser, • Roger Tobin

Clark University Tufts University

What might a learning progression approach for energy look like? • A network of ideas that can develop over time • A scientific stance toward phenomena that can develop progressively over time and allow students to understand energy.

Why Start Learning about Energy in 3rd Grade?

A scientific understanding of energy What are the key ideas? • The Nature and Forms of Energy • Transfer and Transformation • Dissipation

• Conservation

Some challenges to understanding conservation of energy 1. Colloquial references to “conserving” energy appear to contradict conservation of energy.

2. It appears that energy is simply gone when – a ball stops bouncing – a flashlight burns out – hot water cools. 3. Many different units to quantify the same thing

The Teacher’s Perspective Fulcrum Summer Energy Institute for Science Teacher Leaders Goal: Improved understanding of 1. The nature of energy 2. Conservation of energy 3. Conversion of thermal to mechanical/electrical energy

Entry via Thermal Phenomena Heat water using • • • •

A hazelnut A candle Alcohol fuel Electrical current from a battery run through a resistor • Mechanical energy from a frother

Children’s Ideas about energy • Little experience thinking about everyday phenomena or classroom activities in terms of energy transfer. • “Where did the energy go?” - It’s GONE. • A compressed spring does not have energy. • Every object has either kinetic or potential energy. • Batteries have energy.

How can children learn to look at phenomena in terms of energy? The Energy Lens • What changes do I observe? • How do those changes translate into energy changes? • Where does the energy come from? • Where did the energy go? • Where is the dissipated energy? • Is all the energy lost or gained by the system accounted for?

The Energy Lens in Grade 3 What changes do I observe? Change in speed, change in configuration How do I describe what I’ve observed in terms of energy? More speed - more energy of motion The more stretched an elastic band, the more stored energy it has. Where did the energy come from? Energy changes occur in PAIRS When the energy of an object increases, energy of another object decreases.

A “Stepping Stone” for Energy Conservation: Energy gains and losses occur in pairs. If one object or system gains energy, one or more others lose energy.

Begin with transfer of energy from one object to one other object where both forms of energy are the same and changes are clearly visible Progress to transfer of energy from one object to one or more other objects, or the environment, where the forms of energy may be different and may not be easily observed or measured.

How can we represent energy?

Looking at Collisions Through the Energy Lens

How can energy bars help students understand energy transfer?

How can energy bars help students understand energy transfer?

What sequence of activities can help students understand “stored” energy?

The Energy Lens in 5th grade • What physical changes do I observe? • What are the indicators of energy change that I observe? • What corresponding pairs of energy changes can I identify? (If an object gains energy, what others lose energy?) • Where the heck did the energy go? (I can’t see it!)

Videos can help students describe phenomena in terms of energy

How can the Energy Lens help us understand energy gained as heat? • What’s the energy story when the hand-crank generator: – Turns a propeller, – Lights a light bulb, – Charges a capacitor, – Heats a resistor.

• What other ways can you heat a resistor? – a battery – a capacitor – a hand-crank generator

Looking at heat transfer through the Energy Lens • What happens when cold water in a test tube is immersed in a cup of hot water?

Questions 1. What are useful contexts to introduce energy transfer? —e.g., energy in life processes and in burning fuel 2. What tools can help students “see” energy changes that are hard to observe? —Videos —Temperature probes —”Energy meters” and video narration —Particle magnifier Other? 3. How can they learn to represent this abstract entity?

Question

• Where can you use the energy lens in your curriculum?