If you’re a parent, you’ve probably experienced that moment.

You’re emptying school bags, checking lunchboxes, or tackling the weekly laundry when you discover something unexpected:

A pocket full of stones.

A collection of leaves.

A feather.

A stick.

Maybe even a bug that was never meant to make it through the front door.

While these discoveries can be puzzling (and occasionally alarming), child development experts say there’s actually a good reason children are drawn to collecting little treasures from the outside world.

Listen below as HOT1027 Breakfast listeners share the more unusual items they’ve found hidden in school bags, lunchboxes and pockets over the years:

Some stories proved surprisingly sweet. Others left parents wondering exactly what had been happening during break time. But according to experts, these collections of seemingly random objects are often far more meaningful than they appear.

These items are sometimes referred to as “transitional objects” — things that help children process new experiences, explore their surroundings and develop a sense of independence. Whether it’s a shiny pebble from the playground or an oddly shaped leaf picked up on the walk home, these objects can provide comfort while helping children make sense of the world around them.

Experts also say collecting and carrying these treasures encourages creativity, curiosity, problem-solving and even emotional regulation. In short, that mysterious collection rattling around in a school blazer pocket may be serving a far greater purpose than simply creating extra work for parents.

The stories shared by HOT1027 listeners are a reminder that childhood curiosity comes in many forms. For children, those random treasures often represent adventures, discoveries and memories. For parents, they’re usually a surprise waiting to be found at the bottom of a school bag.

Either way, the next time you uncover a pocket full of rocks, you might want to think twice before throwing them away.

To your child, they could be priceless.