Electrical conductors and insulators: what children learn
Will a bulb light through a paper clip or a plastic ruler? A free Grade 3 science game about electrical conductors and insulators, with a printable game and worksheet.
Suggested grade 3 practice, selected by skill and reading demand. US states and schools teach these topics in different grades; this is not a state-standards alignment claim.
Next Generation Science Standards teaching connection: PS3.B: electrical energy transfer. Conductor vocabulary can prepare learners to explore electric circuits. The linked Grade 4 expectation requires evidence about energy transfer; sorting materials alone does not demonstrate that performance. Read the framework.
How to play
Sort the cards into the right groups. Tap a card, then its group. You can also drag a card, or press the number on its group. Each game has 3 rounds with no timer. Every card is checked as soon as you place it: a card in the wrong group comes back with a hint, and you get a point for each card you place right first time. For a quicker go, choose Quick quiz: 10 multiple-choice questions in 120 seconds (choose Relaxed for more time).
Step by step
- Ask "Is it a metal?". Metals such as copper, iron, steel, aluminum, brass and gold are good conductors.
- If not, it is probably an insulator. Plastic, rubber, wood, glass, paper, cork and fabric are insulators.
- Picture the circuit. Put the object into a gap in a circuit with a battery and bulb. If the bulb lights, the object is a conductor.
- Think about safety. Wires are metal inside (to conduct) and plastic outside (to insulate), so electricity stays in the wire.
- Don't mix up magnets and electricity. All metals conduct electricity, but only iron and steel are magnetic.
Worked examples
Example 1: Which of these is a good electrical conductor: a cork, a cotton sock, aluminum foil or a wooden spoon?
Working: Only one of these is a metal. Aluminum is a metal.
Answer: Aluminum foil.
Example 2: Is a rubber band a conductor or an insulator?
Working: Rubber is not a metal. It is used on tool handles and wire coverings to keep electricity in.
Answer: An insulator.
Example 3: Why are wires covered in plastic?
Working: The metal inside carries the electricity. Plastic is an insulator, so it stops the electricity reaching our fingers.
Answer: To keep electricity in the wire and keep us safe.
Common mistakes and how to fix them
- Thinking only magnetic metals conduct. Test a brass key or foil in a circuit: they are not magnetic but the bulb lights.
- Thinking water is an insulator. Tap water conducts electricity, which is why we never touch switches with wet hands. Water is left out of the quiz because very pure water conducts poorly, which is confusing.
- Thinking "insulator" only means keeping warm. Insulators slow down heat or electricity. Many electrical insulators (wood, plastic) are good heat insulators too.
Activities to try at home
- Look at a plug or charger together (unplugged). Point out the metal pins and the plastic case.
- Make a list of things in the house made of metal and things made of plastic, and say which conduct.
- Talk about electrical safety: why we never poke things into sockets and never touch switches with wet hands.
- Print the worksheet and ask your child to give a reason for each answer.
Ideas for the classroom
- Build a simple circuit tester (battery, bulb, wires with crocodile clips) and test a tray of materials.
- Record results in a table and look for the pattern: all the conductors are metals.
- Challenge students to find a non-metal that conducts (pencil graphite) and discuss why it is special.
- Use the game as an assessment after the practical.
Free printable game and worksheet
The free printable starts with a game sheet, such as a color-by-answer picture, an answer maze or a secret-code joke, followed by a worksheet. Both use the same checked questions as the online game, and the answers are on the last page. Print it, or save it as a PDF from your browser’s print menu.
Open the free printable game and worksheet
Frequently asked questions
Is a pencil a conductor?
The wooden case is an insulator, but the "lead" is graphite, which conducts electricity. Graphite is a rare non-metal conductor, so it is a fun extension rather than a quiz question.
Is the human body a conductor?
Yes, our bodies conduct electricity, which is why mains electricity is so dangerous. Only ever investigate with batteries.
Are conductors of electricity also conductors of heat?
Mostly, yes. Metals are good conductors of both, which is why a metal spoon in hot soup gets hot quickly.