Why does popcorn pop?Explained for kids

The short answer

Every popcorn kernel holds a tiny drop of water inside a hard shell. When it gets hot, the water turns into steam, the steam pushes until the shell bursts, and the soft white inside puffs out into popcorn.

Try these at dinner

What's hiding inside every popcorn kernel?
What makes it pop?

What Nana says

Movie night! Popcorn ti... Whoa! Hey!
Do you want to know how this tiny kernel... turns into this big fluffy popcorn? Let's find out!
Look. Inside, there's soft white stuff. And right here... a tiny drop of water.
Now the microwave heats the water. It gets hotter... and hotter... and turns into steam!
Steam needs lots of room. But this shell is hard. There's nowhere to go!
So the steam pushes... and pushes... and...
The soft white stuff puffs up and turns the kernel inside out. That's popcorn!
So every popcorn is a tiny water explosion.
Ten minutes of popcorn. Three days of finding it in the couch.
Quiz time, Opa! Ready?
What's hiding inside every kernel?
A drop of water! That's right!
And what makes it pop?
Steam pushing! Kernels don't get scared.
Next time you make popcorn with a grown-up, listen closely. Every pop is a tiny drop of water turning into steam!
Time for a little nibble!
"Even small things can make a big pop."