How can I explain Pigeon Hole Principle to a child in a simple manner? There is a exhibition in our school.I took up mathematics part in the exhibition. all types of people will be there. can anyone suggest me how can i explain PHP to small children ?? how can i make it interesting to them??

Say you didn't fold your laundry last time so all of your socks are mixed up in your drawer. Now you only want to leave the house if you are wearing matching socks. If you have $7$ pairs of socks then clearly if you remove $8$ socks from the drawer youll have at least $1$ matching pair.