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Electromagnet Investigation: Free Printable Worksheet for Year 8
- ForYear 8
- StageKey Stage 3
- CostFree
- FormatPrintable PDF
Electromagnet Investigation is a free printable science worksheet for Year 8 (ages 12 to 13), in Key Stage 3. Students plan a fair test and find out whether the number of turns of wire in a coil changes how many paper clips an electromagnet can lift. It takes about 30 minutes, and page 2 gives the grown-up notes, help ideas, a stretch task and the answers.
It comes from the Mini Minds Hub, the free library of printables from Jaques of London, the British games and toy company that has been making games for families since 1795. Print both pages, give page 1 to the students and keep page 2 for yourself. Black and white printing works well.
What is on the sheet
Students use a results table with columns for coil turns, three separate tests of clips lifted, and a mean. They record what their electromagnet picks up, repeat each test, and work out an average. There are lines for writing, so they can explain how they kept the test fair and give a conclusion that uses their own evidence.
- Coil turns
- Clips: test 1
- Clips: test 2
- Clips: test 3
- Mean
Worked example: finding a mean
An electromagnet lifts 8 clips, then 11 clips, then 8 clips in three tests. What is the mean?
This example uses different numbers from the sheet. It shows two ways to find a mean.
Method 1: add, then divide- Add the three results: 8 + 11 + 8 = 27.
- Divide by the number of tests: 27 ÷ 3 = 9.
- Guess a middle value, such as 9.
- Compare each result with 9: 8 is 1 below, 11 is 2 above, 8 is 1 below.
- The differences cancel out (1 + 1 = 2 below, 2 above), so 9 is the mean.
Setting up the investigation
Gather the equipment
You need insulated wire, an iron nail, a low voltage battery and a pot of paper clips. An adult checks that the battery is low voltage and that the wire is in good condition.
Plan the fair test
Decide what to change, what to measure and what to keep the same. Write the plan on the lines before anyone starts building.
Test and record
An adult makes and breaks the battery connection. Students count the clips held, write the result in the table and repeat for each test.
Look at the results
Work out each mean, then look across the table for a pattern. Write a conclusion that points to the numbers.
What is an electromagnet?
An electromagnet is a magnet made by passing an electric current through a coil of wire. Often the coil is wound around an iron core, such as a nail. The magnetic effect is there when the current flows, and it can be switched off. That is why electromagnets are useful in machines that need to pick things up and then let them go.
Investigations like this build the working scientifically strand of the Key Stage 3 curriculum. Students choose a variable to change, measure an outcome, repeat readings and draw a conclusion from evidence. Repeating tests matters because single results can be unusual. Taking a mean gives a fairer picture than relying on one attempt.
A grown-up should supervise the battery and wires. Use a low voltage battery only and never mains electricity. Wire can get warm, so an adult checks it is not hot to touch and disconnects the battery between tests. Adults do the connecting and disconnecting.
Electromagnet facts
- An electromagnet can be switched on and off, which a permanent magnet cannot.
- An electromagnet needs an electric current flowing through its coil to work.
- Scrapyard cranes use large electromagnets to lift and drop iron and steel.
- Electric bells use an electromagnet to make the clapper move.
- Wire used in coils is often coated with thin insulation so the current follows the wire.
Skills and curriculum link
- Fair testing
- Recording results
- Calculating a mean
- Spotting patterns
- Writing conclusions
Ideas to help with the investigation
- Change one thingIn a fair test, only one variable is changed on purpose. Everything else stays the same so the result can be trusted.
- Repeat the testRepeating a test shows whether a result is typical or unusual. It also gives you numbers to find a mean from.
- Agree how to countDecide before you start how you will count clips, so every test is counted in the same way.
- Use the evidenceA conclusion should refer to the numbers in the table, not only to what you expected to happen.
Key words
- ElectromagnetA magnet made by passing an electric current through a coil of wire.
- CoilWire wound into loops, called turns.
- VariableSomething that can be changed or measured in an investigation.
- Fair testA test where only one variable is changed and the others stay the same.
- MeanA type of average. Add the results, then divide by how many results there are.
- ConclusionA statement that answers the question, using your evidence.
How to use it
- Print both pages. Page 1 is for the students. Keep page 2, which has the notes and answers.
- Read the question together and gather the equipment. An adult checks the battery is low voltage and the wire is safe to use.
- Plan the fair test first. Talk about what changes, what is measured and what stays the same.
- Carry out the tests in a pair or small group, taking about 30 minutes. An adult handles the battery connections. Students count and record each result.
- Work out the means and write a conclusion. Check against page 2, then talk about what you would improve.
Help, stretch and game ideas
If it feels too hard
Give students the table with the first column already filled in. Let them record one test at a time, then repeat before moving on. Say the plan aloud first: what we change, what we measure, what stays the same.
To stretch confident children
Plot a graph of coil turns against mean clips. Then investigate a second variable, such as the number of batteries or the thickness of the nail. Explain which variable you kept fixed this time and why.
Make it a game
Challenge: whose electromagnet lifts the most clips with only 20 turns? Each pair tweaks its design, such as the nail or how tightly the wire is wound, then tests it. Compare results and explain what helped.
Mistakes to watch for
Watch forStudents change the number of turns and also swap the nail or battery.
Try thisWrite a list of everything that must stay the same. Tick it off before each test.
Watch forStudents add the three results to find the mean but forget to divide.
Try thisRemind them that a mean is the total shared equally. Divide by the number of tests.
Watch forThe conclusion says what students expected, not what they found.
Try thisAsk them to quote two numbers from the table, then write the conclusion again.
Talk about it
- What are you changing, and how will you keep everything else the same?
- Why do we repeat each test instead of doing it once?
- What would you do if one result looked very different from the other two?
- How did you decide how to count the clips?
- What does your table show? How do you know?
- How could you make this investigation more accurate?
Take it off the page
Everyday electromagnets
Look around the home or classroom for devices that might contain an electromagnet, such as a bell or buzzer. Write a list and talk about why switching on and off is useful.
Fair test planner
Choose a different question, such as how far a paper plane flies. Write what you would change, measure and keep the same.
Mean practice
Collect three measurements, such as hand spans or jump lengths, and find the mean of each. Compare with a friend.
Who it is for
Parents
Read the question together and let your child lead the planning. Keep the equipment simple and do the battery connections yourself. Ask them to explain each choice, and praise careful thinking.
Teachers
Use it as a practical lesson on fair testing, a lesson on tables and means, or a homework task with a write up. Pairs work well. Page 2 has support and stretch ideas for mixed ability groups.
Home educators
Pair this with books or videos about electricity and magnetism. A short session of about 30 minutes works well. Use the stretch idea to turn it into a longer project, with a graph and a second variable.
Where this fits
Before this, students meet magnets and forces and simple electrical circuits in earlier years. They also learn to take careful measurements and record them in tables.
After this, students go on to study magnetism and electricity in more depth in Key Stage 3 physics. The same fair testing and data skills carry forward into later science, including GCSE work on magnetism and electromagnetism.
Questions parents and teachers ask
- What age is Electromagnet Investigation for?
It is written for Year 8 (ages 12 to 13), in Key Stage 3. It also works as revision for older students or a stretch task for confident younger ones, with an adult supporting the practical.
- What will students practise?
Students practise fair testing, recording results in a table and finding a mean. They also write a conclusion about whether the number of coil turns changes how many paper clips an electromagnet lifts.
- How long does it take?
It takes about 30 minutes. The time includes planning, testing, working out the means and writing a conclusion. A pair or small group works well, and you can split the activity over two sessions.
- Is it safe to do at home?
Yes, with an adult in charge of the practical. Use a low voltage battery only, never mains electricity. An adult connects and disconnects the battery and checks the wire is not hot to touch.
- What if it feels too hard?
Give students the table with the first column filled in. They record one test at a time and repeat it before moving on. Planning aloud first also helps.
- Is it suitable for teachers to use in class?
Yes. Teachers can use it as a practical lesson, a table activity or a homework task with a write up. Page 2 has notes, help, a stretch idea and the answers.
- Do I need to print in colour?
No. It prints well in black and white on plain A4 paper. It is free to print again for brothers, sisters, other groups or revision a few weeks later.
Preview the full PDF
Made by Jaques of London, making games for families since 1795. A printable supports classroom learning and does not replace a teacher.