Zooming Hearts – a fun Valentine’s Day science activity kids love!
This is such a cute and fun science activity for Valentine’s Day (or any day)! Can you make a paper heart zoom? If you’re sneaky with the dipping part, you can also make it look like a cool party trick and amaze your friends. Science magic!
This activity is fun for a bunch of age groups, from preschoolers to grade school kids. Jewel is 9 and Bumble Bee is 7 in the videos below – they can easily do all the elements without help, but they still found it fun!
How to make a heart zoom
*Note: affiliate links to similar products used are included below
I love that this is one of those fun activities you can whip up in under 10 minutes, and that it only uses everyday items you probably already have at home. It also makes a perfect indoor science project for a rainy day!
- a shallow tray or plate
- red paper
- dishwashing liquid (aka dishsoap) in a small bowl
- red food colouring (optional)
1. Add enough water to cover the bottom of a plate or tray. Add food dye if you are using.
2. Pour dishwashing liquid into a small bowl.
3. Cut out small paper hearts. We like to fold the paper and cut half a heart out along the fold, which opens up to be a full heart. (Our hearts are more symmetrical when we do it that way!)
4. Drop a paper heart into the water and see what happens. (This is the ‘control’ part of the demonstration or experiment). Hopefully it will float and not move around too much!
5. Predict what will happen if you dip a heart in dishwashing liquid first, and then drop it in the water. (This is the ‘hypothesis’ part).
6. Test it out. Dip the tip of a paper heart into the dishsoap, and then place it in the water. It should zoom!
(Note: To duplicate the experiment, you’ll need to replace the water each time.)
7. Experiment! Do the results change with different sized hearts? Do different brands of dishsoap affect the result? What about using other liquids (eg olive oil). Be sure to carefully record your results. This would make a great science project!
8. Share your findings in the comment section below!
Here’s a video of three of our attempts…
What’s happening here?
Water has surface tension. You can see it when you look at a water drop, and it bulges up a bit. That’s what allows a regular paper heart to float on top of the water.
Soap breaks down the surface tension of water – this is one of the reasons why soap makes a good cleaner. So when the heart dipped in dishsoap touches the water, the surface tension is reduced, and the water wants to spread out flat. As the water spreads out, it pushes the heart along, so that it looks like it is zooming across the plate.
We have a bunch of heart-themed science ideas your kids will LOVE over on our Valentine’s Day Science & STEM projects page, including:
- how to make heart-shaped bubble wands. But the sciencey question is – can you make heart-shaped bubbles?
- how to make a Borax crystal inter-locking hearts necklace – Jewel loved this one.
- how to make salt crystal heart decorations that are really sparkly!
If you liked this activity, you might like to follow Go Science Kids and Fun Science for Kids boards on Pinterest.
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