Why Getting Dirty Might Be the Healthiest Thing Children Can Do

An article shared by Ms. Karoliina, Academic Director of HEI Schools

Dear Parents and Caregivers, 

At HEI Schools, we see every mud stain as a beautiful sign of learning. Science shows that playing in the dirt is like a natural 'vitamin' for your child’s immune system and a 'spark' for their creativity. We promise to keep them safe and help them clean up afterward, so they can enjoy the best of both worlds: the freedom of nature and the comfort of home. Let's celebrate these messy, happy moments together!

In the heart of our modern, bustling cities, we have created a world that is increasingly paved, polished, and plastic. For many children, "play" has moved indoors or onto sterile, rubber-matted surfaces. As an educator who has walked through forest schools in Finland, Australia and urban campuses in Vietnam and Saudi Arabia, I have observed a growing silence where there used to be the joyful squelch of mud and the busy digging of small hands. At HEI Schools, we believe it is time to invite the "mess" back in. We see "dirt" not as something to be scrubbed away, but as a vital, life-giving element that nurtures a child’s body, mind, and spirit.

1. The Invisible Shield: How Nature Builds Children’s Immunity

Wall-less classrooms at HEI Schools Saigon Central

One of the most common worries I hear from parents is the fear of germs. It is a natural instinct to want to keep our children clean and safe. However, modern science is now telling us a surprising story: an environment that is too clean can actually leave a child’s immune system unprepared for life.

This is best explained by the "Biodiversity Hypothesis." Our immune systems evolved over thousands of years in constant contact with the natural world, the bacteria in soil, the microbes on plants, and the dust in the air. When we remove these from a child’s daily life, their "immune army" becomes bored and under-trained. It starts overreacting to harmless things like pollen or peanuts, leading to the rise in allergies and asthma we see in urban areas today.

A landmark study in Finland provided the "gold standard" evidence for this. Researchers replaced the gravel and asphalt of city daycare yards with real forest floors, lush with moss, sod, and soil. Within just one month, the children playing in these "rewilded" spaces showed a much higher diversity of healthy bacteria on their skin and in their guts. Their bodies were literally building a stronger, more intelligent shield against illness. At HEI Schools, when we encourage children to garden or explore the earth, we aren't just playing; we are providing a natural "vaccination" for their long-term health.

2. A Symphony for the Senses: Dirt as a Learning Tool

At HEI, we often say that "Learning is everywhere and all the time." When a child sits in a patch of dirt, they aren't just "getting messy" they are engaging in a high-level laboratory experiment. Unlike a plastic toy that only has one button and one sound, natural materials like mud, sand, and water are "open-ended." They can become anything the child imagines.

Getting dirty is sometimes a way of learning

From the perspective of Cognitive Development, these messy experiences are essential. When a child picks up a handful of damp earth, their brain is processing a mountain of data: How heavy is it? Is it grainy or smooth? What happens if I add more water? Does it smell different when it's wet? This is sensory integration at its finest.

In our HEI approach, simple puddle can spark a week-long investigation into physics and biology. Children learn about "viscosity" as they stir mud, and "perseverance" as they try to build a dam. They observe the tiny insects that call the soil home, sparking a sense of wonder and empathy for living things. These aren't lessons they can learn from a screen or a worksheet. They are lessons they "feel" in their bones and hold in their hands.

3. The "Happiness Bacteria": Emotional Well-being in the Garden

There is a reason why children (and many adults) feel a sense of peace when their hands are in the garden. Science has found a remarkable little resident in the soil called Mycobacterium vaccae. This non-pathogenic bacterium has a curious effect: when we touch it or breathe it in, it stimulates our brain to release serotonin - the "feel-good" hormone.

In the fast-paced, high-pressure environment of modern Vietnam, children often carry invisible stress. They are expected to learn fast and perform well. The simple act of "getting dirty" acts as a natural pressure valve. At HEI Schools, we foster a "Culture of Trust" where we tell the child: "I trust you to explore. I trust you to get messy. I trust your curiosity."

When a child isn't worried about keeping their clothes pristine, they are free to be fully present. This freedom builds a deep sense of self-confidence and emotional regulation. They learn that they can interact with the world, change it, and explore it without fear. This "earthy" happiness is the foundation of a resilient spirit.

4. A New Way of Living: Sustainability Starts in the Soil

Natural materials are prioritized in every lesson

Finally, we must think about the world our children will inherit. We cannot expect a child to care for the environment if they have never truly touched it. Our "Sustainable Way of Living" principle starts with a connection to the earth beneath our feet.

When children spend time getting their hands dirty, they develop what we call "Ecological Literacy." They understand that the soil grows their food, that the rain feeds the soil, and that every tiny bug has a job to do. By allowing them to get dirty, we are helping them fall in love with the Earth. And we protect what we love.

At HEI Schools, we balance this exploration with gentle routines. We teach children to wash their hands carefully and respect their belongings after play. This teaches them that we can be "adventurers" in the mud and "responsible citizens" in the classroom.