Where does sand come from?

Think of a sunny day at the beach. You scoop up a handful of warm sand. It trickles through your fingers, soft and tickly.

Sand stretches all along the shore, more than you could ever count. So where does all that sand come from?

Sand begins as hard rock. Picture a boulder, which means a rock even bigger than you. It sits at the edge of the sea, right where the waves splash.

The waves crash against the boulder, again and again. Each wave gives the rock a strong push. In the end, the water cracks small pieces off the boulder.

Those small pieces become pebbles. The waves roll them back and forth, so they knock against each other. Clack, clack, clack! What do you think happens to pebbles that bump and rub all day long?

They get smaller and smaller! Every bump rubs off a little bit of stone. So the pebbles shrink, one bump at a time.

At last the bits get so small you can hardly see one. Each bit is a grain, which means one teeny speck of rock. Heaps of grains together make sand.

All this bumping and rubbing takes a very long time, longer than your grandma has been alive. Through all those years, the waves keep the new grains rolling in the water.

The waves carry the grains and drop them on the shore. The grains pile up there. In time, they make a soft, wide beach.

Waves crack a big boulder into pebbles. Then they rub the pebbles down into tiny grains of sand.

Along the shore, the waves slide up and set down their grains, soft and warm. Each tiny grain was once part of a big, hard boulder.