These 25 science fair project ideas for kids are grouped by grade, and each one is written as a question your child can actually test at home. For every idea you get the one thing to change and the thing to measure, plus the steps of a good project, display board tips and how much a parent should help.
How to pick from these science fair project ideas for kids
A strong project starts with a question that can be answered by measuring something. Let your child choose a topic they already care about, such as plants, sport, food or gadgets. Then check that you have the materials at home and enough days before the fair, because plant projects need two weeks or more.
Science fair projects for grades 3 to 4
1. Which paper towel soaks up the most water?
Change: the brand of towel. Measure: how much water is left in the cup after dipping one sheet.
2. Does more water make a bean sprout faster?
Change: spoons of water given each day. Measure: days until the sprout appears and its height.
3. Which paper plane design flies farthest?
Change: the fold design. Measure: distance flown, averaged over five throws.
4. Which wrapping keeps an ice cube frozen longest?
Change: the wrapping, such as foil, cotton cloth, newspaper or nothing. Measure: minutes until fully melted.
5. Which floor surface makes a ball bounce highest?
Change: the surface, such as tile, carpet or grass. Measure: bounce height from the same drop height.
6. Does water temperature change how fast sugar dissolves?
Change: cold, room temperature or warm tap water. Measure: seconds until the sugar disappears.
7. Do plants grow toward light?
Change: where the light comes from, using a box with a hole on one side. Measure: the direction and amount of lean after a week.
8. Which foil boat shape carries the most coins?
Change: the shape of the boat. Measure: coins held before it sinks.
Science fair projects for grades 5 to 6
9. Does string length change how fast a pendulum swings?
Change: the length of the string. Measure: time for ten full swings.
10. Which surface slows a toy car the most?
Change: the surface at the bottom of a ramp, such as cloth, sandpaper or plastic. Measure: distance the car rolls.
11. How much salt does it take to float an egg?
Change: spoons of salt stirred into the water. Measure: the number of spoons at which the egg first floats.
12. Does lemon juice stop apple slices going brown?
Change: the coating, such as nothing, water, lemon juice or salt water. Measure: a browning score from 1 to 5 every ten minutes, with photos.
13. Does colour change how warm water gets in the sun?
Change: the colour of paper wrapped around identical glasses. Measure: water temperature after one hour.
14. Does more baking soda make more gas?
Change: teaspoons of baking soda added to vinegar in a bottle. Measure: the distance around a balloon stretched over the neck.
15. Which soil holds the most water?
Change: the soil type, such as sand, garden soil or clay. Measure: water that drains through in five minutes.
16. Does background music change how many words people remember?
Change: silence or music while reading a list. Measure: words recalled out of fifteen. Ask every volunteer for permission first.
17. Which paper column shape holds the most weight?
Change: the column shape, such as triangle, square or cylinder. Measure: books stacked before it collapses.
Science fair projects for grades 7 to 8
18. How does temperature affect yeast?
Change: the water temperature in a bottle of yeast and sugar. Measure: the size of a balloon on the neck after thirty minutes.
19. Do more coils make an electromagnet stronger?
Change: turns of insulated wire around an iron nail, powered by one AA battery. Measure: paper clips lifted. The wire warms up, so connect it for a few seconds only, with an adult present.
20. Which kitchen liquids are acids and which are bases?
Change: the liquid tested with red cabbage juice, such as lemon juice, vinegar, soapy water or baking soda water. Measure: the colour against a colour chart. An adult prepares the juice. Use food and soap only, never cleaning chemicals.
21. How does ramp height affect the speed of a rolling ball?
Change: the height of the ramp. Measure: time to cover one metre, then calculate the speed.
22. Which material is the best insulator?
Change: the wrapping around cups of warm tap water. Measure: temperature every five minutes for half an hour, drawn as a line graph.
23. Does the colour of light affect plant growth?
Change: the colour of clear plastic film over each plant. Measure: height and number of leaves over two weeks.
24. Is your writing hand quicker to react?
Change: the hand used to catch a dropped ruler. Measure: the centimetre mark where it is caught, averaged over ten tries.
25. How does salt affect how fast water freezes?
Change: the amount of salt in each cup of water. Measure: whether each cup is liquid, slushy or solid, checked every twenty minutes in the freezer.
What judges look for at each grade
| Grade band | What judges look for |
|---|---|
| Grades 3 to 4 | A clear question, a simple fair test, neat results, and a child who can explain the project in their own words. |
| Grades 5 to 6 | A hypothesis with a reason, repeated trials, a table and a graph, and a conclusion that matches the data. |
| Grades 7 to 8 | Controlled variables named, accurate measurements with units, averages, sources of error, and ideas for further testing. |
Rules differ between schools, so read your own fair's judging sheet first.
The steps of a good science fair project
- Question. Write one question that can be answered by measuring.
- Hypothesis. Predict the answer and give a reason: "I think the longer string will swing slower because it has farther to travel."
- Fair test. Change only one thing. Keep everything else the same, and repeat each test at least three times.
- Results. Record every number in a table as you go, then draw a bar or line graph.
- Conclusion. Say what the results show and whether the hypothesis was right. A wrong hypothesis is still a good project.
Projects with graphs are also good practice for math, since your child will use averages, units and scales.
How to make the display board
Use a three-panel board and lay it out so it reads left to right.
- Left panel: question, hypothesis and materials.
- Centre panel: the title in large letters, photos of the test, and the graph.
- Right panel: results table, conclusion and what you would do next.
Keep sentences short and print or write large enough to read from two steps away. Use photos of the experiment, not of your child's face. Bring the notebook and, if allowed, the model itself.
How much should a parent help?
Think of yourself as the lab assistant, not the scientist. Your child chooses the question, does the testing, records the numbers and writes the board.
You can help by buying materials, handling anything sharp, hot or electrical, taking photos, asking "what did you notice?" and keeping the schedule on track. If you are tempted to fix the handwriting or redo the graph, stop. Judges talk to the child and quickly see who did the work.
If your child wants a guide for the thinking, Core Minds Academy teaches live online classes, 1:1 or in pairs, including a science program. You can book a free trial class and bring the project question along.
