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Cheap and Easy Science Fair Projects

Sam has been a firefighter for 9 years. He currently serves as lieutenant and public information officer of his city's fire department.

Quality Time With the Kids

Parents are always on the prowl for ways to spend more time with their children and motivate them at the same time . I can remember sitting at the kitchen table as Mom tried to explain fractions to me. Homework is a great way to get to spend time with your child in a productive way. Helping a kid with their homework builds a strong family connection.

The science fair project may be the holy grail of homework assignments. Science fair projects allow Mom and Dad to spend ample time interacting with their child and developing a relationship. It is a bond that will last a lifetime. I recall working on my volcano with my dad and just how much fun we had. The biggest problem is this: What do you build?

How Air Expands When Heated

I am going to help you solve that problem with some simple, yet effective projects that will not cost you an arm and a leg.

This first one is very simple. It will demonstrate how air, when heated, will expand. You will need a few things.

  • A bottle
  • A coin that will rest on the mouth of the bottle without falling in
  • A small amount of water
  • Your refrigerator

Mind you, the fridge is not needed when you do this at school, there you can just keep your bottle in a cooler of ice.

Here are the steps for our first experiment.

  1. Put the bottle in the in the fridge to let it get good and cold. This is a great time to talk with your kid and ask them how they are doing in school. Remember quality timeis essential.
  2. Take out the bottle.
  3. Place the coin over the mouth of the bottle, be careful not to drop it in.
  4. Now use your finger to dab a little water around the edges of the coin. Kind of make a seal between your coin and your bottle's opening.
  5. Now grasp the bottle firmly, not bending it, between both your hands.
  6. After you see the coin frantically jumping, you can remove your hands.


You just witnessed the expansion of air as a direct result of the warmth from your hands. As your body heat warmed the cold air inside the bottle it caused it to expand and try to escape the opening. The coin acted like a gate and thus began to move.

The Volcano

The grand daddy of all science projects has to be the volcano. So many variations exist. Nothing seems to get the job done quite like a huge volcano erupting in a classroom. First and foremost you need to build your volcano. I find that using play dough or modeling clay is the best way to go. This can be picked up at Dollar Stores or if available a Dollar Tree, and you will have enough to make several attempts at this.

Build your volcano with as much detail as you want and then take a common pill bottle. (Parents make sure it is cleaned) and place it in the top of the volcano to act as the opening and lava chamber. You can use a cup or any container really but I went with a pill bottle so there you go.

For our experiment we are going to use two different recipes for the lava. Here are the items you need to have on hand. Most are common household items that you should have lying around the house.

  • Lemon juice
  • Vinegar
  • Baking soda
  • Liquid dish soap
  • Water
  • Red food coloring
  • Cups
  • Spoon

Now we are ready to make some lava. Gather all your materials where they will be easy to get to. Here are our steps in order.

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  1. Mix into one cup 1 tablespoon of baking soda.
  2. Now add 1 tablespoon of dishwashing liquid.
  3. Next pour in 1/4 cup of water (I prefer bottled).
  4. Now add three drops of your red food coloring.
  5. Pour this mixture into the volcano.
  6. Now for the grand finale, pour in 1/4 cup lemon juice to the volcano and watch as the action unfolds.

You now have a working volcano, but what about one that really kicks?

Now do all of the above, but instead of using lemon juice, substitute 1/4 cup of vinegar and watch what happens.

This project is great because it really allows the kid to be creative. They could decorate the volcano with houses or trees. It really lets them shine.

Fun With Static Electricity

We all have had the experience of touching something or someone after rubbing our feet across a carpet. Now you can demonstrate the power of static electricity as a magnet! This is a simple and easy project you can set up to teach your child how static electricity works. The items you need are simple and are probably already in your home. You will need

  • Salt
  • Pepper
  • A comb

First start by mixing together salt and pepper on a table. Here are our steps for this easy project.

  1. After you mix the salt and pepper, put in on a table top.
  2. Now get out your trusty comb.
  3. Rub the comb on a cloth or even through your hair a few times.
  4. Now hold the comb just over your mixture and watch.

What happens?

The pepper is lighter. It will be attracted to the comb and attach itself to the comb. This is happening because when you rubbed the comb through your hair you created a build up of static electricity that acted in many ways like a magnet. Short and simple yet highly effective.

Egg in a Bottle

This little trick never fails to get the attention of anyone. How can we fit a hard boiled egg into a glass bottle when the opening is not big enough to do it? While it may sound difficult it really is quite simple. You will need some props for this one.

  • A glass bottle (milk bottles are great)
  • A hard boiled egg, peeled of course
  • A match (adult supervision needed!!!)

Light your match and drop it into the bottle. Now place the egg on top of the opening and wait. Suddenly some unseen force starts pulling the egg into the bottle. What could it be?

This one is simple yet very thought provoking. In reality you have created a vacuum. As the match burns the fire it produced is consuming the oxygen in the bottle. Soon the oxygen is depleted completely thus creating a vacuum. The vacuum effect sucks the egg into the bottle.

This is a prime way to demonstrate air pressure buildup.

There You Go!

Easy, cheap, and fun ways to spend time with your kid all the while teaching them a little science. I hope you enjoy and have a great time trying these.

Questions & Answers

Question: What is the best cheap science project?

Answer: The volcano would probably be your cheapest bet.

Question: In the science fair volcano project, what can we get as observations and conclusions?

Answer: This link should help.


Sam Little (author) from Wheelwright KY on April 25, 2018:

Thanks for reading it. I am glad you enjoyed it.

Chrish on April 24, 2018:

Thank u for this

Sam Little (author) from Wheelwright KY on March 20, 2013:

Will be praying and thanks for the kind words.

Muttakin Rashid Alvi on March 20, 2013:

Thanks , sir! Love your work! Tomorrow is my science fair. Pray for me.

yeso on March 11, 2013:

tanxsoo much

Sam Little (author) from Wheelwright KY on December 29, 2012:

You could use them as such if you wanted to. Let me know how it goes.

quran on December 28, 2012:

is this 6 grade


Sam Little (author) from Wheelwright KY on November 18, 2012:

Thank you very much. I was the science nerd in school and thanks to my ambition I did a few hundred dollars damage to our library when my volcano had an extra ooomph added to it. It was worth it though.

suziecat7 from Asheville, NC on November 18, 2012:

Great fun ideas. I remember the science fairs from grade school. Mine was about dying fabric with natural products. It was a disaster. :(( Great Hub - voted up and shared!

Nijha Smith on March 03, 2012:

You guys have awesome and easy projects! They don't cost a lot of money, they are fun, and they are very interesting.


Sue on January 10, 2012:

Cool and neat home projects that demonstrate scientific principles, however, not good for science fair projects. No data to collect. :( Science fair projects have to have data and a variable that can be changed.

xyavier on August 19, 2011:

wat kind of page is this,this is os awsome how to get an egg into a bottle. i never heard of that before man this is so cool.

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