The curious mind of a preschooler barely rests. Knocking things to the floor just to see what will happen when they do is a rite of passage for any toddler. The best, and most fun, way to learn about it is through simple gravity experiments. Although we can’t see gravity, we can feel its effects. It’s the reason things fall when you drop them and what keeps our feet firmly planted on the ground. 

Explaining gravity to a five year old or preschooler is easier when you do it through hands-on exploration. Engaging your children in critical thinking, problem solving, innovation and creativity through STEM activities is the perfect way to educate while also entertaining them.

Bottle Drop Gravity Experiment

Suitable for Ages 4+

Even before Isaac Newton, folklore has it that a trailblazing scientist named Galileo made an amazing discovery by dropping two balls from the world’s most famous building malfunction: the Leaning Tower of Pisa in Italy. He discovered that when he dropped two balls of the same size (but slightly different weights) they hit the floor at the same time.You would think the heavier object would fall faster, but he proved that gravity makes falling objects move with the same acceleration, no matter how heavy they are. 

This idea was even tested (and confirmed) in space. When, during the Apollo 15 moonwalk in 1971, an astronaut dropped a hammer and a feather at the same time they fell at the same rate, despite their different shapes and weights, because there was no air resistance. 

Fast forward to the modern world and we’re able to test out the theory using water bottles.

A series of images showing a gravity experiment using water bottles: two bottles being decorated then filled up with varying amounts of water; the bottles being dropped from a height.

What You'll Need 

‍Instructions‍

Step 1: Take two identical water bottles and decorate them with stickers (just for fun!), then fill one bottle completely with water and put a small amount in the other one.

Step 2: Find somewhere high, a balcony or outdoor staircase, and drop the two water bottles at the same time. Did they hit the ground at the same time?

Hot Tip: Ensure you have a sturdy bottle with the lid on tight. Always check the ground below is free of people, pets or objects before launching this gravity test. Dropping from great heights could see a bottle split, so best to use waterproof drop sheets or venture outside. Always supervise your child with height experiments. 

Questions to Spark Curiosity

  • Why did the bottles hit the ground at the same time? 
  • Does dropping from higher up change how they hit the ground?

‍

Did You Know? The bigger an object is, the more gravity it has. That's why the Earth has a strong pull, and it keeps the Moon in orbit around it. Gravity is like a universal magnet that brings things together, and it's what makes the planets go around the sun. Sir Isaac Newton – the mathematician behind the three famous Newton’s Laws of Motion – was the first to identify this universal force circa 1665, after conducting his own gravity experiments by watching an apple fall from a tree. He laid the foundation for our modern understanding of gravity.

SEE ALSO: Paper Plane Flight Challenge for Kids

Paint Pendulum Gravity Experiment

Suitable for Ages 5+

A pendulum is basically an object that can swing freely using the force of gravity. Historically it was used as an accurate form of timekeeping (think of the ding dong chimes of a grandfather clock) but here we’ve used a pendulum to make beautiful art, while thinking about science, of course.

A GIF series displaying a hole being poked in a cup, string tied through top of cup to hang it high, then a swinging cup holding paint making pattern on paper.

What You’ll Need

Instructions

Step 1: Get a paper cup and make two holes on either side near the top rim of the cup.

Step 2: Cut a piece of string about 1m long, then tie each end through the holes. 

Step 3: Make a hole in the bottom of the cup (this is where the paint will drop out, so don’t make it too big). 

Step 4: Find somewhere level to hang your pendulum (a broom handle across the back of two chairs works well), then put a large sheet of paper underneath. 

Step 5: Fill your cup with watered-down paint. Either place sticky tape over the bottom hole or simply use a finger to stop the paint leaking out until you are ready to launch. Let go of the pot and give it a little swing to make sure you get the full kaleidoscopic effect.

Hot Tip: Drop sheets, and launching this experiment outside under your supervision, means if little Picasso hands get expressive with painting – the clean-up will be quicker!

Questions to Spark Curiosity

  • How does gravity work in this experiment?
  • Where does the pendulum move fastest, and where does it slow down?

Marble Run Gravity Experiment

Suitable for Ages 5+

The classic marble run is a great experiment to learn about gravity and explore other concepts like kinetic energy and friction.

Not only that, it can be built with almost anything: cardboard rolls, old cereal boxes, plastic bottles, basically anything that a marble will roll down. You don’t even need marbles; you can simply roll your own made from air dry clay or playdough – that’s what we did!

GIF series showing cutting cardboard rolls, lining with white tape, cutting diagonal slits into cardboard, positioning rolls in slits, dropping clay marble down the run. 

What You'll Need 

Instructions

Step 1: Find a piece of thick cardboard to mount your marble run onto, then take your time to mark precisely where the ramps will go. Remember to consider that the marble will gather speed as it descends – when the marble gets closer to the bottom, it won’t simply drop straight down – so position the tubes to allow for that. 

Step 2: Once you have a run that looks good to you, cut the tubes in half and tape them lightly to the board to give it a test run. Did the marble bounce out? Do any of the tubes need to be repositioned? Now is the time to make your adjustments. Testing and refining your design is called the prototyping stage and is essential in the design process; some of the best designs in the world go through intensive testing and modifications. 

Step 3: Once you are happy with your design, stick down your tubes more firmly and let the marbles drop. 

Hot Tip: The construction of this experiment can be quite fiddly. Kids and parents will need to team up to get this one rolling.

How to Explain It to the Kids 

While your child tests the marble run, it’s a good opportunity to point out that gravity is the force pulling the ball down the slope. When it comes to friction in gravity, there’s an easy way to explain it to your youngster: “If you rolled a marble down a grassy hill, it would move more slowly or get stuck unlike a slippery dip where it would speed down fast. The grass has more resistance or friction because it is rougher than a smooth slippery dip.”

Questions to Spark Curiosity

  • Do you notice what happens when you let the marble fall?
  • Which materials do you think would slow the marble down if we put them in the tubes?

SEE ALSO: 4 Construction Activities for Kids Who Love to Build

Centre of Gravity Experiment

Suitable for Ages 5+

Our mass and weight activities have so far taught us that gravity is the force that keeps our feet on the floor (and makes marbles drop, pendulums swing, etc) but what about the ‘centre of gravity’? This is a special spot inside everything (think your child’s favourite toy, a carrot or a craft stick) where, if they could put their finger right there, it would be perfectly balanced and not fall over. So, if explaining to your children, the centre of gravity is like a secret balance point that keeps things from tipping over! Our next experiment explores this complex concept using very simple ingredients. 

GIF series for centre of gravity experiment; wrapping pipe cleaner around popsicle stick, tying beads to ends, then balancing popsicle stick with beads hanging down on a wooden rod. 

What You'll Need 

Instructions

Step 1: Take a craft stick and wrap a pipe cleaner around it. 

Step 2: Add weights to each side (we used wooden beads, but you could also use pegs or anything that you can attach to the ‘arms’). 

Step 3: Now it’s time to make your creation walk the tightrope. Suspend a pole horizontally using a clamp, or put it between a pile of books and a tabletop. From here, adjust the position of the pipe cleaner until a perfect point of balance is achieved – this is the centre of gravity. 

Hot Tip: This experiment can be tricky, especially when adding, adjusting and balancing the weights. A steady adult hand is a must.

Questions to Spark Curiosity

  • What happened when we balanced the stick upright with the weights on the end?
  • Will adding one more bead to one side change the balance?

SEE ALSO: STEM Activities for Preschoolers that Teach Problem Solving

Parachute Gravity Experiment

Suitable for Ages 5+

Parachutes are a simple, but incredible (and life-saving) invention, used by skydivers, astronauts, and even rescue teams to land safely. Once the parachute opens it captures the air around it, descending slowly and softly. As with the other gravity experiments, the one we made is very easy to build, but follows the same principles of those used in modern-day, high-tech military operations. 

A GIF series of images showing hands folding tissue paper, punching a hole in the corners, tying string through to make a parachute, attaching a toy, and launching the parachute. 

What You’ll Need 

Instructions

Step 1: Cut out a square of tissue paper and add sticky tape to each corner to ensure the paper doesn’t rip when any force is applied. 

Step 2: Make a hole in each corner using a hole punch. 

Step 3: Cut four equal lengths of string and tie them to each corner, before pulling them all together and tying a knot in the bottom.

Step 4: This is where you will attach your thrill-seeking parachutist. You could use a toy figure that can be dropped on the floor, a peg or piece of clay.

Step 5: Now it’s time to launch your parachute. Find a higher point, like a balcony or the top of the stairs, to drop it from. Alternatively, just throw it high in the air – as long as the parachute has time to open, it will work. 

Hot Tip: Tissue paper easily rips, so best you’re on hand to help with construction and cutting.

Questions to Spark Curiosity

  • What did you notice when we threw the parachute in the air?
  • What do you think would happen if the toy is heavier or lighter?

‍

This was originally published in September 2023 and has been updated.