Asked by families

12 questions families bring to the science fair, each with a project to try.

The fair is tomorrow and we have nothing. What can we do tonight?

Pick a project that tests in one sitting and gives a quick number: the paper towel soak test takes about forty minutes, three kinds of towel and a teaspoon. Do three tries each, fill in the printed table, and make a simple board with the question, the table and one sentence on what happened. A small honest project beats a big unfinished one.

Try: 🧻 Which paper towel soaks up the most water?

Is a baking soda volcano a real science fair project?

Only if you change something and measure it. A volcano that just erupts is a demonstration. Change how much baking soda goes in, measure how high the foam climbs three times at each amount, and it becomes a real test with a graph.

Try: 🌋 Does more baking soda make a bigger fizz?

My child's hypothesis was wrong. Will they lose points?

Not with a fair judge. A hypothesis is a guess you test, and finding out it was wrong is a result. What judges look for is a conclusion that uses the numbers honestly and says what to test next. The conclusion sheet has a box for "not right" on purpose.

Try: 🧊 What melts ice fastest: salt, sugar or sand?

How many times should my child repeat the test?

Three tries at every level is the usual minimum, and every project here asks for it. One try can be a fluke (a car bumps a chair leg, a cube melts on a warm plate). From 4th grade, add the three and divide to find the mean for each level.

Try: 🚗 Does a steeper ramp make a toy car go farther?

What's a good first science fair project for a 1st grader?

One with an answer you can count or see. Floating pennies in foil boats is a favourite: fold three boat shapes, count the pennies each holds before it sinks, three times each. A grown-up can do the writing; the counting and the guessing are the child's.

Try: ⛵ Which boat shape carries the most pennies?

My 7th grader says the projects look too easy. What makes one harder?

A second variable and a careful look at error. Take the pendulum: first test string length, then keep the length and change the weight. Two lines on one graph, a mean for every point, and a sentence on what could have thrown the numbers off makes a middle school project.

Try: 🕰️ Does a longer string swing slower?

We have two weeks. Which project makes the most of them?

One that grows, because the logbook fills itself and judges love a day-by-day record. Bean seeds with different amounts of water take about ten days, and a dated line each day (what I did, what I saw, what I think) shows the work happened over time.

Try: 🫘 How much water do bean seeds need to sprout?

Can my child do a taste test on the family?

We leave every project that tests people out, taste tests included, because the rule sets we read say projects with people need a review and consent first. Ask your child's teacher; many schools allow a family-only version with no names. Here, test the food instead of the people: which dip keeps an apple slice from going brown?

Try: 🍎 What keeps a cut apple from going brown?

Why are there no projects with pets or bugs?

Live animals are not allowed at most elementary fairs, and projects that test animals need forms and a review at every level up to the international fair. Plants make a good swap: they grow, they react, and a bean plant leaning toward the window gives real numbers.

Try: 🌱 Do plants bend toward the window?

How much should I help without doing it for them?

Keep your hands on the safety and the schedule, and theirs on the science. Read the steps aloud, hold the ruler, pour the hot water, and ask questions: what did you keep the same, how do you know? The words on the board should be your child's, even if you held the pen.

Try: 💎 Which grows crystals faster: salt or sugar?

Do we need to buy anything?

Almost never. Nearly every project here uses what most houses already have, and the page says the cost at the top. The paper bridge needs paper, books and a pile of pennies, and nothing else.

Try: 🌉 Which paper bridge shape holds the most coins?

It's winter. Can we still do an outdoor project?

Pick one that needs sun, not warmth. Shadows through the day work on any clear winter day, and the low winter sun makes long shadows that are easy to measure. Measure at 9, noon and 3, and never look at the sun itself.

Try: 🌤️ How does a shadow change through the day?

👨‍👩‍👧 For grown-ups and teachers: how much to help, the safety rules, and running a school fair. Science fair v0.16.1 · Checked 6 November 2026.