This popular Valentine’s Day science activity is a holiday variation of the classic magic milk experiment. It’s a little bit science, a little bit art, and a whole lot of fun!
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Magic milk is one of our favorite science activities because of the endless possibilities for creation. The kids love watching the colors erupt, scatter, and mix. It is sometimes unpredictable, which makes it exciting and new each time. Add some heart shapes and you have a Valentine’s Day science activity that is irresistible.
Milk (We used whole since that is what we had in the fridge, but any kind of milk will work.)
A bowl, casserole dish, or baking sheet
Liquid dish soap
- Place a heart cookie cutter in a dish or baking sheet.
- Pour milk into the cookie cutter. It will leak out into the dish, and that is fine. You don’t want or need much, just a thin film that covers the bottom.
- Squeeze a few drops of food coloring or liquid water colors into the milk. Add glitter, if desired.
- Dip the end of the toothpick into the dish soap and then into the center of one drop of colored milk. Don’t stir it! Watch the color erupt and swirl inside the heart.
- Repeat and enjoy.
Valentine’s Day Science Explained
Why do the colors explode when you add dish soap to the milk?
Put simply, the dish soap interrupts the molecules at the surface of the milk, making them spread out. This makes the colors spread out, leaving a beautiful marbled pattern behind. You can read my full explanation here if you are interested. The science behind what you see in magic milk is pretty fascinating!
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