The Best Science Fair Project Guide and Experiments (that actually work!)

Are you wondering what to do for your School Science Fair? You want to do something cool and fun, you want to “wow” the judges with your research and presentation, but you don’t know where to start? Look no further. We’ve put together some information and links to help guide you so you can harness your inner scientist and rock that fair.

Of course, there are necessary steps to having a good science fair project. The scientific method is key and it is the best way to find out, or investigate, more about the world. Let’s go through the process:

  • First, you must choose a topic. Make sure it is one that interests YOU, the science kid! Don’t let your parents do the work for you. Do you like space? Airplanes? Flowers? Pennies? Worms? Snow? Burritos? Sports? Find an interesting topic and get started. You’re more likely to finish your project if you are motivated, or interested, to do it.
  • Ask a question (or several questions) about that topic that you want to answer. Why is it important to know the answer to this question? If it helps, start with questions like “Which (blank) helps (blank) do best?” or “What can I add to (blank) to help (blank)?” For example “Which liquid helps plants do/grow best?” or “What can I add to an egg to help protect it from breaking when I drop it from 6 feet high?” See ( . You can ask household questions like “What kind of detergent washes the most stains?” or if you have a pet you can test “what food does my pet like best?” 
  • Research your topic and question and keep track of all your information sources, or references.
  • Come up with a hypothesis, or a reasonable guess, for your question. Use the information you got from your references to make that prediction.
  • Design a procedure, or experiment, for that question. How will you measure your results? You want to be as accurate as possible and try to control as much of your environment as you can so you’re only changing one thing (or variable) at a time. For example, if you want to compare what helps plants grow best, do an experiment where you have 2 of the same plants in the same soil and pot and the same location/environment and only change what you add to grow them such as water vs. lemon juice. You can add more variables such as soda or grape juice, just try to make it so that you can prove that the only reason the plant grew better/worse is because of that different variable.
  • List and gather the materials you need to carry out your experiment.
  • Do the experiment. Sometimes you may need to repeat your experiment and double check your measurements just to make sure it actually works and gives you the same results.
  • Observe and record the data. Write down what happened in the experiment. What did you see? Which variable caused a different result?  
  • Analyze your data. Find out if your hypothesis, or guess, was right or wrong. It’s absolutely okay if you didn’t correctly predict the results. Many scientific discoveries happen by accident and were not expected by the scientists who did the experiment. This is what makes it so exciting! Just make sure you report your data and explain it as best you can.
  • Try and come up with new questions based on the results of your experiment. How can you improve your experiment in the future?

So now you have guidelines. But of course you will need to make a poster to present your methods and findings. Here’s a few links for making the perfect science fair poster. Be sure to include lots of pictures and make sure your words are legible so the judges can understand what you did. And be prepared to answer any questions they might have. That is why you need to know about your topic.

So now you know about what it takes to do a science fair project. Are you still trying to figure out what topic to do? Is it too intimidating? Let us help. Here are a few great science fair projects from around the web that you can try for yourself.

Experimenting with UV Sensitive Beads

You use UV-sensitive beads which change color when exposed to dangerous rays to understand how the Sun produces different wavelengths of light and what materials can protect us from those potentially harmful waves.

As a bonus question, you can use different SPF sunscreens to cover the beads and see if that helps protect them from the harmful UV rays. You can really tell why your parents say it is important to put on sunscreen when you go outside on a sunny day or at the beach!

This experiment helps you understand the concept of water density and whether the ocean (or saltwater) helps things like boats and animals float and why. This is an easy one and you can test different salt levels to prove whether having more or less salt makes the water more or less buoyant. Be sure to keep track of your measurements!


Want to know why it’s important to visit your dentist so often? Here’s a very cool experiment using eggshells to simulate teeth enamel, the stuff that covers your teeth. You can soak the eggs in different substances with different amounts of sugar and see how they affect the eggshells. As a bonus, you can test to see how brushing with toothpaste and toothbrush actually helps after you’ve gotten them nice and dirty. You’ll never look at sugary drinks the same way.

Here’s a neat experiment to understand why it is important to wash your hands and how to see microbiology in action. You use actual Petri dishes and establish the scientific need for having a control (untouched) sample. It’s both super gross and very cool at the same time! Try to think of other variables you can test as well! 

In this experiment, you gather lots and lots of dirty pennies and test out different household acids in order to clean them. Why do they get like that and what ingredient cleans them the best? This is a great chemical reaction that leaves you feeling shiny and bright! 

If you don’t mind getting your hands dirty, here’s a cool zoology project that’ll show you why Earthworms are important and what happens to dead plants in the soil. After your project is done, you can place these guys in your garden and let them add nutrients to your soil!

Who doesn’t love engineering a paper airplane? Yes, it is considered engineering when you design a machine (or paper) to fly. Pick a few different fun designs of paper airplanes (Check out and then measure how far each design will go. Try to predict which one will fly the furthest or which one will fly in a loop. What things about each airplane do you think affects its flight? Research about aerodynamics and remember to double check your measurements!

This one lets you experiment with different textures and see how it affects how far a marble can roll. What exactly is friction and how does it affect distance traveled by an object? Check this cool experiment out and see for yourself!

We really hope this helps you on your search for the perfect science fair project for you! Please let us know what you decide to do and if any of our information was helpful. No matter what, please keep on asking questions about the world around you. That is what science is all about!

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