Crazy-color Milk

  

Science is defined as the systematic knowledge of the physical or material world gained through observation and experimentation. 

 

Children are some of the greatest observers and most enthusiastic experimenters that I’ve ever encountered.  If you’ve ever taken a painfully slow walk with a two-year-old or seen kids floating sticks down spring-melt rivers on curbsides, you know exactly what I mean.

 

So……the next activity I want to introduce is a science experiment.  Don’t be afraid!  It is easy to do and my kids LOVE it!  They would do it once a week if I let them.  We call it crazy-color milk.  I got the idea at  http://pbskids.org/dragonflytv/, which is one of my favorite websites.  Check it out if you get a chance.

 

All you need is a small, shallow dish or plate, milk (2% or whole milk work best, but skim milk works too,) dishwashing liquid, Q-tips and food coloring.  I would also recommend putting down newspaper and having your child wear an apron or old shirt.  I think that food coloring stains. 

 

First, add enough milk to cover the bottom of the dish. 

 

In a separate small container, mix together about a half cup of water with a squirt of dish-soap (a teaspoon or so.) 

 

Have your child put several drops of different colors of food coloring into the milk (maybe two drops of each color.)

 

 

 

Finally, have your child dip a Q-tip into the dish-soap mixture and touch the Q-tip to the milk.  The detergent will break the surface tension of the milk and the food coloring should swirl around in interesting patterns. 

 

 

 

 

Let them play with it!  It works better if they don’t stir, but just keep re-wetting their Q-tip with soapy water and touching it to the milk.  You can even compare how it works with skim milk versus whole milk.   Have them draw a picture of it in their lab notebook!

 

Explain to your child that the surface of liquids is sort of like a stretched elastic skin, like a balloon full of air. This property of liquids is called surface tension.  When the skin of the liquid is broken, whatever is underneath will be able to escape, like the air rushing out of a balloon. 

 

In this experiment, the surface of the milk was the elastic skin and the detergent broke the “skin” of the milk.  Food coloring escaped from underneath the milk’s surface when the surface tension was broken.

 

Remember, science is fun, not scary!   Encourage your child to be curious about the world around them.  Every child is a scientist, whether they know it or not!

 

 

 

 

 

Tags: science for kids