Do you have a morning routine that you follow to get ready for school in the morning? If you’re like most kids, you probably do. Get up. Take a shower. Get dressed. Eat breakfast. Grab your backpack. Head out the door.

Wait! You forgot to fix your hair! You don’t want to get to the bus stop with a head full of crazy hair. Of course, many kids spend several minutes each morning fixing their hair so that it looks just right.

Along with the clothes you wear, your hairstyle is one of those parts of your appearance that you can easily change to create a different look whenever you feel like it. If you have naturally-curly hair, you can straighten it. If you have naturally-straight hair, you can curl it.

If you want to curl your hair, what do you reach for? The curling iron, of course! And what about if you want to straighten your hair? You’ll probably reach for a flat iron or the blow dryer. Have you ever stopped to think that all of these tools use heat to get very different results? How does that work?

You probably don’t necessarily think about science when you’re curling or straightening your hair, but you should! A few basic scientific principles explain what’s going on when the curling iron or blow dryer give you the fabulous hair you’ve been wanting.

Your hair is made up of, among other things, keratin proteins, natural oils, and hydrogen bonds. These ingredients work together to give your hair its natural shape, color, etc. People with different hair types and styles will have different amounts and arrangements of these items.

If you have straight hair, you can’t just curl it around your finger to make it curly. The hair’s composition, particularly its hydrogen bonds, will return it to its normal state quickly. Have you ever noticed that it’s easier to bend many items if you apply heat to them? Your hair works in the same way.

When you use a blow dryer or a curling iron, the heat it produces breaks down your hair’s hydrogen bonds, stripping away its natural oils and proteins. The heat changes your hair’s texture, allowing you to mold it to create the look you want.

The shape of a curling or flat iron helps to mold your hair into the shape you desire. As you hold your hair in a particular shape for a few seconds, the bonds begin to reform into the new shape you want. The bonds will tend to hold your hair in its new shape until they’re broken down again.

One of the ways they can be broken down other than heat is by water. That’s why you shouldn’t be surprised if your carefully-straightened hair turns curly again if it rains or the weather is particularly hot and humid.

Wonder What's Next?

We think tomorrow’s Wonder of the Day will really move you!