Walking Rainbow Heart Experiment: Valentine’s STEM

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INSIDE: Looking for fun and cool Valentine’s Day experiment? Check out Walking Rainbow Heart Experiment and answer the question can water walk upwards against the force of gravity? Your kids will love the wow factor of colourful experiment that is perfect for kids of all ages!

Valentine’s STEM

Can water walk up against gravity? Well no, not really. But in this experiment it will look like coloured water is truly defying the laws of gravity by traveling up and over into an entire new cup! Such a fun and easy way to explore science.

Walking Rainbow Heart Experiment: Valentine's STEM

Looking for more Fun Valentine’s Day Crafts or Activities? Check out these fun ideas:

Exciting Sensory Bins for Curious Kids

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Boring afternoons are made exciting with awesome animal-based bins, like Salty Shark Bay or Yarn Farm. Pretend play bins like Birthday Cake Sensory Play or Bubble Tea Party encourage creativity and imagination. And your kids will have so much fun they won’t even know they’re getting smarter with STEAM (science, technology, engineering, art and math) activities like Sink or Float Soup, Magnetic Letter Hunt or Ice Cream Scoop and Count.

Walking Rainbow Heart: STEM Activity

Grab 6 equally sized clear drinking glasses or plastic cups. Next, grab some paper towel. I found that the Bounty Select-a-Size worked best as it gave you the right amount of paper towel needed for this experiment. If you don’t have this brand simply cut the normal sized paper towel in half. Fold it in half length wise and the fold it again in half. You may need to cup some off the end so that extra paper towel is not left in the air while it rests in the cups. Test this before putting in the water or food colouring and off the extra amount off the end.

Walking Rainbow Heart Experiment: Valentine's STEM

Cut out the shape of a heart from red construction paper and place it on the table. Invite your little one to recreate the shape using the cups by placing the cups all around the heart to make a heart shape with the glasses.

Walking Rainbow Heart Experiment: Valentine's STEM
Walking Rainbow Heart Experiment: Valentine's STEM

Next, add water and food coloring into the 1st, 3rd and 5th cups. I filled my glasses about 3/4 way. Add 3 drops of red food colouring into the first cup, 3 drops of yellow into the 3rd cup in the heart shape and 3 drops of blue in the 5th cup. There should be a cup without food colouring in between each colour.

Walking Rainbow Heart Experiment: Valentine's STEM

Place a sheet of folded paper towel into each cup connecting it with the cups on either side of it. Again make sure the paper towels aren’t sticking up too much. Also make sure that the cups are touching each other.

Walking Rainbow Heart Experiment: Valentine's STEM

Observing the Walking Rainbow Heart

At this point I asked my kids what they thought was going to happen. My 7 year old guessedthat the colours were going to mix to create new colours. We went through each new colour that would be created. Then we stood back and waited. Immediately the paper towel started to absorb the coloured water and its started creeping up the paper towel. We watched for a little while but then they got bored and we decided to go and do another science experiment for Valentine’s Day but would come back periodically to observe what had happened.

Walking Rainbow Heart Experiment: Valentine's STEM

As the paper towel absorbs the coloured water and it meets another primary colour a new colour is made! My kids came back periodically through out the afternoon to check out their results!

Walking Rainbow Heart Experiment: Valentine's STEM

This was a lot of fun and a great way to talk about colour mixing with my preschoolers and the science behind this experiment – capillary action.

Walking Rainbow Heart Experiment: Valentine's STEM

The Science Behind Walking Rainbow Heart Experiment

The water creeps up the paper towels through the process of capillary action. The paper fibers in the paper towel provide small gaps through which the water is about move through. The water is able to move upwards against gravity because the gaps in the paper towel act like little tubes pulling the water upwards.

The adhesive forces between the water and the fibers of the paper towel have more force than the cohesive forces between the water molecules. Thus, the water moves up and across the paper towel out of one glass and into another.

Walking Rainbow Heart Experiment: Valentine's STEM

Age Suitability for Walking Rainbow Heart Experiment

This activity is great for kids 3 years and up. My kids are 3.5, 3.5, and 7.5 year old.

Supplies for Walking Rainbow Heart Experiment

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  • 6 clear glasses
  • Red, Yellow and Blue food colouring
  • Paper Towel
  • Water

Make quiet time their favourite time!

Play is at the core of learning during the early years and it can take many forms. One of the most important of these is sensory play because it engages all of a child’s senses (taste, touch, smell, sight and hearing) and has a enoumous positive impact on brain development.

My Sensory Play Kits are a fun and easy way to keep your child engaged while at the same time capitalizing on the benefits of sensory play to nurture their mind!

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