There are structures all around you that have been built by other people. The house or apartment that you live in, the school where you attend, the library, the treehouse, the bridges you travel across.

And there are the structures that you build yourself. You may build with blocks, with sticks that you find, with old cans or pieces of garbage, or perhaps the tallest building possible with all of the old playing cards that you find in your grandparent's house.

Structures are created when you pile up all of your stuff and make a fort, or when you find an abandoned box on the road and make it into a secret hideaway.

Just look around and you will see built structures that you use or pass by each day and think about all of the structures that you make.

How tall can you build a house of cards?