Magic Milk Fireworks are a surprisingly simple Fourth of July science activity that kids will beg to repeat over and over again. With just a few common ingredients, they’ll turn ordinary milk into an explosion of red, white and blue fireworks. It’s perfect for Memorial Day, Fourth of July… or anytime you need a guaranteed boredom buster!
To prep, I gathered a few simple supplies:
- A plate or baking dish
- Milk (We used whole milk, since that is what we drink, but any kind of milk will work.)
- Star cookie cutters
- Red and blue food coloring
- Liquid dish soap
Create Magic Milk Fireworks
Next, we poured some milk onto our dish. We didn’t need a lot – just enough to cover the bottom. Then each kid placed a star cookie cutter in the milk.
I dripped a few drops of red and blue food coloring inside the stars and told the kids to get ready for the really FUN and AMAZING part!
My son dripped one drop of liquid dish soap right in the center of the star. We watched in amazement as the colors scattered in all directions, just like Fourth of July fireworks!
I added a few more drops of food coloring to watch it mix in. Then we removed the cookie cutters and sat in awe as the colors burst into the rest of the milk in the dish!
Patriotic Magic Milk Science
There are a few different science concepts to learn from this activity. First, dish soap disrupts the surface tension of the milk. All liquids have chemical bonds along the surface that make the liquid form a little dome on top. You can see this effect when a droplet of water rests on wax paper. Adding soap interrupts those bonds along the surface, making the surface molecules spread out and the colors explode like fireworks!
Second, soap has some really interesting properties. One end of a soap molecule LOVES water (hydrophilic) while the other side HATES water and loves oil and fat (hydrophobic).
Soap can get dishes and clothes clean because the hydrophobic end picks up the grease, oil, and dirt, while the hydrophilic end dissolves in water and washes all the dirty stuff away with it.
Milk, especially whole milk, contains fat and proteins. When soap is added to milk, the hydrophobic end of a soap molecule grabs onto a fat molecule in the milk.
With millions of molecules finding a partner all at once, the mixture gets all stirred up!
More Science Boredom Busters
Keep the fun and learning going with 30 of our favorite kids’ science experiments under the sun! The best part is that they only use common household supplies like baking soda, salt and milk!