Before you start reading I would like to clarify something about this post. The idea behind this sensory stem experiment was to see if we could make different jello color combinations to explore colors with a sensory side to it. The blending colors part was a bit of a “fail” but it was so much fun and it opened up the chance to talk about colors while experimenting with our sense of touch. And because STEM is all about making mistakes and learning from them I wanted to share this with you anyway. Even though the colors won’t mix properly, you still see certain hints of new colors and it is a great way to engage your child in some messy sensory play. A heads up, it can get really messy so I would suggest to do it outside and have some old towels to wipe your kid’s hands.

But for now, I will share the experiment with you and the activity as it was still a very fun way to talk about colors! And with a failed experiment you also learn something, so it’s a great way to teach this to your kids too. So I will describe the preparation and then suggest a few ways you can guide the experiment to create some learning from it.
Preparation
My daughter helped me prepare the jello beforehand so she was very excited to do the experiment later. This type of motivation is great for any experiment! At this point, you can introduce the experiment and make some hypotheses of whether or not mixing the jello will mix the colors. Write your hypothesis down for later, or any other thoughts you might come up with. Time to prepare our experiment!
Things you will need for the preparation:
- Clear jello mix
- Food coloring (we just used the primary colors: red, yellow and blue)
- Small containers to separate colored jello
Prepare the jello following the instructions on the package, before putting into the fridge, separate into small containers and add food coloring, mix with a spoon until it’s dissolved and has a strong color. Once the jello has cooled down, it is time to start the experiment!
Fun Color Experiment
So let’s go ahead and take a look at what the experiment could look like. The idea was the following; to mix jello with food coloring and once it gets cold try to mix different color jello to make new colors. I know now that once jello gets cold you can’t really mix it together and therefore you can’t blend colors (I’m sure there is some science behind that and I will look into it to update the post in the future). Things you will need for the sensory STEM experiment:
- Colored jello
- Big bowls where the mixing magic will (or will not) happen (we used 2)
- Old towels or cloth that you don’t mind getting dirty to wipe off the jello
Now it’s time to have some messy playful fun! Bring out the colored jello and try mixing different colors (with your hands!) in the bigger bowls and see what happens. It is so good for children to feel different textures and playing with jello is quite interesting! It is very beneficial to use your senses when learning and while they have their hands in the jello you can have some good talks about colors!
Observation and conversation guide for the experiment
The main thing to do with toddlers is talk, talk, talk. Have conversations about what is happening, make observations. This will help build vocabulary. The term “hypothesis” might be a bit over their heads but you can start to use the concept. Ask them if they think colors will mix and write a big YES or NO. Color-code it for better understanding, YES-Green or NO-Red. Put your prediction on the fridge and go explore other things until it is ready. Just like real experiments that usually require time, jello takes time to cool down.
Next up, when it’s time for the experiment, grab your “hypothesis” and all the jello containers. Put it all out and let the mess begin! I suggest saving some containers for later and just letting your kids play first. If possible, you can try answering following questions:
- What happens to the colors when we mix the jello? Is your paper right or wrong?
- Does it mix better or worse with different combinations of colors? (try all three combinations and see if there are any differences)
- What actually happens?
- Why do you think it happens?
Feel free to get messy too and observe while your toddler plays. Point things out and start some color conversations. Here are some suggestions of observations you can make and what you can talk about:
- Look at what happened when I mixed these colors!
- If your kid is receptive, you can explain the colors you have and introduce the concept of primary colors
- Ask your kid to pass you some colors. Can I have the blue and yellow? What do you think blue and yellow make?
- Explain color combinations and what new colors they create (you will see a faint hint of new colors when mixing the jello)
And that’s it! A simple color experiment that will keep your children entertained and will allow them to “feel” colors! I hope you can enjoy this experiment with them and if anyone knows what the scientific concept behind the jello color not mixing please let me know in the comments!
Want to know how to transform your STEM activities at home? Check out this post:
Other fun activities to sneak in some STEM learning:
Happy STEM learning!

