Water science is awesome! This water density experiment with sugar uses only a few kitchen ingredients but produces an amazing science experiment for kids!  Water experiments for kids make great play activities as well as learning too!  Enjoy finding out about the basics of color mixing all the way up to the density of liquids with this one simple water density experiment.


Make a rainbow sugar water density tower with a few common ingredients. This colorful sugar water density activity is fun for science experiement for kids!

We love science, but even more, we love science experiments that can be done with inexpensive supplies straight out of our kitchen cupboards. Our science activities for preschoolers are perfect for families, teachers, and everyone on a budget.  Provide awesome science activities for young kids without the expense!


Kids are curious and always looking to explore, discover, check out, and experiment to find out why things do what they do, move as they move, or change as they change!

Science learning surrounds us, inside and out.  Kids love checking things out with magnifying glasses, creating chemical reactions with kitchen ingredients, and of course exploring stored energy!

Looking for easy to print activities, and inexpensive science experiments? 

We have you covered…

Click below to get your quick and easy science activities. 

There are lots of easy science concepts that you can introduce kids to very early on! You might not even think about science when your toddler pushes a card down a ramp, plays in front of the mirror, laughs at your shadow puppets, or bounces balls over and over again. See where I am going with this list! What else can you add if you stop to think about it?

Science learning starts early, and you can be a part of that with simple science experiments with everyday materials.

This easy science activity also makes a cool St Patrick’s Day Rainbow!



  • 4 Glasses or cups
  • warm water and 1 cup measuring cup
  • sugar and measuring teaspoon
  • food coloring
  • spoon and baster 
  • test tubes


STEP 1:  Set out 6 glasses.  Measure 1 cup of water into each glass. This is a great time to explain the importance of all the glasses having the same amount of water!  You can read more about the scientific method for kids.

STEP 2: Add a few drops of food coloring to each glass of water.  You could have your child mix the colors or help them with mixing the colors!

Note: From experience we have found 4 colors is the easiest to work with!

water density experiment

STEP 3.  Measure and add a different amount of sugar to each glass of colored water. We have since cut our experiment down to just 4 colors but you can experiment with all of them.


STEP 4.  Stir until as much of the sugar is dissolved as possible.

You can also make a crystal rainbow that is a great activity for all ages!

STEP 5.  Time to use your baster or pipette to create a colorful rainbow in a jar.

Tip: Have your child try two colors for an easier version!

  • Squeeze the baster and put it in the red water. Release a little of the pressure to suck up some red water.
  • Keeping it squeezed, transfer to orange, release a little more to suck up some orange water.
  • Continue to do this for all the colors. Make sure you leave enough pressure in the baster to get you through all six colors.

My husband perfected the method! We love using basters for many of our science activities.

density of water


Density is all about compactness of stuff in space. For this experiment, the more sugar in each glass of water, the greater the density of the water.   Same space, more stuff in it!   The denser the substance, the more likely it will sink.  This is how our rainbow sugar water density tower works!

By increasing the amount of sugar in the solution but keeping the amount of water constant, you create solutions that have increasing densities. The more sugar you mix into the same amount of water, the higher the density of the mixture.  So density explains why the colored sugar solutions stack on top of each other inside the baster.

You could vary this water density experiment by looking at the density of different concentrations of salt dissolved in water!

YOU MAY ALSO LIKE: Viscosity Experiment For Kids

Looking for easy to print activities, and inexpensive science experiments? 

We have you covered…

Click below to get your quick and easy science activities. 


NOTE: This is probably a better experiment for elementary school or with a very patient kid. My son enjoyed trying to make the tower as well as simply experimenting with mixing colors.

This rainbow sugar water density tower does take a slow hand and patience. You could also try a density tower with a variety of liquids or even a homemade lava lamp to learn more about density.

easy rainbow experiment

We used a test tube from our favorite science kit! This time we found starting with the densest water {purple} worked the best.

STEP 1:  Use the baster’s measuring marks to ensure you get the same amount of each color. Add the purple to the tube.

STEP 2:  Next, add the blue, but add the blue very, very slowly.  You may want to release the water slowly along the side of the jar or glass..

STEP 3:  Continue to do the same thing,  working your way back through the colors. Slow and steady. We practiced a few times before we got a full rainbow.

You can experiment with your own methods and challenge your kids to come up with their own plan of action to make a rainbow in a jar.

artificial rainbow

We kept our artificial rainbow around for a couple days It’s so pretty in the light!

Awesome science experiment for kids you can try today! Pull out sugar, water, and food coloring and get started experimenting!


density tower explanation


Grow Your Own Rainbow Crystal

What Color Is A Mirror?

Rainbow Slime

Colors For Kids With Slime

Rainbow Alphabet Puzzle

How Are Rainbows Made

Skittles Rainbow

Preschool Science With Rainbows

Rainbow Science Math Activities St Patricks Day

Looking for easy to print activities, and inexpensive science experiments? 

We have you covered…

Click below to get your quick and easy science activities. 



  1. Hello! I tried this experiment with my students today with little success 🙁
    The purple and blue separated perfectly, but when green was introduced, it all mixed together from there on.
    Any thoughts? I’m so disappointed!! Your’s is PERFECT!!!

  2. Hello, Iam a science teacher too. Thanks for sharing this experiment with us. But there is a point that ı cannot understand.

    To make in a baster, squeeze baster and put in red water. Release a little of the pressure to suck up some water. Keeping it squeezed, transfer to orange, release a little more to suck up some water.

    I cant understand these sentences because my english level 🙁 Should I make the test tube oily before pouring the colors? In addition Should I use syringe to take the colored waters in order to pour them? if you can explain i will be really grateful

  3. I found this worked well when I added 4 drops of food colouring per glass rather than 2 drop per glass which I tried first. Try adding milk after, the result is really interesting!

  4. Ours did not work at all. Huge flop even though we followed the directions explicitly. Very frustrating. Super messy. Unsuccessful.

  5. The key is to make sure your sugar ratios are all different so they layers separate and you do need to be slow and patient adding in the layers.

  6. We put a cup of sugar in the purple, half a cup in the blue, quarter cup for green, two tablespoons for yellow, one for orange and none for red. Slowly dribbling each color down the side of the test tube was key to avoid mixing layers.

  7. You can use it with a mix of ages but I think it’s best for early elementary age kids. You can add our free science journal page to it as well.

  8. So I tried to do the experiment and I found that if you actually add the different amounts of sugar to Gatorade colors it works for better results.

  9. We tried this experiment with 6 colors, a turkey baster and a large glass cylinder. Epic fail. Brown sugar water was our result.
    We found your instructions, tried again and has great success! We used 4 colors, a pipette and shot glasses and it worked beautifully! Adding the subsequent layers VERY slowly was key. The turkey baster had a tendency to dump too much water at a time. The pipette was easier to control. Thank you!

  10. It is a bit more challenging than most of our activities. Starting with just 2 or 3 colors might help!

Comments are closed.