A focused energy settles over the forest. Surrounded by lanky white pines and a golden carpet of fallen needles, children ages 4 through 10 are building forts with fallen logs.

Today, the forts are not coming together easily. The logs are wet and heavy. The kids are tired. Yet, the students are handling their frustration with patience, solving problems with teamwork and ingenuity. The teachers offer help when large batches of kids can’t lift a fallen log, but mostly the kids wave them away.

“We want to do it ourselves,” they say.

Slowly, slowly, they balance the logs in a lean-to position against a tree. They strengthen the fort with more sticks, use needles to fill in gaps to block the wind.

The forts are finished. They are strong. The kids are muddy and tired and very, very proud.

Fort building seems simple, but the learning happening today is filled with engineering, physics, geometry and history, all fueled by engaged social-emotional learning. Nature and students are working together to reach that beautiful, sacred space where kiddos are deeply engaged, directing their play.

Journalist and advocate for nature play David Sobel describes forts as the physical representation of a child’s rich inner world and right to privacy.

In my own work as a nature teacher, forts are the most loved invitation that I offer. When I ask a kid if they want to build a fort, an inner light shines and they, usually silently and with eagerness, move to a pile of fallen sticks and logs and immediately get started. For young ones hesitant with nature, this is one of the best beginning nature activities.

When teaching how to build a fort to those entirely new to the construction, I model with small twigs the lean-to style fort: a large log leaning at an angle from the Y-joint of a tall tree to form a triangle and then other logs and sticks leaning against the ‘spine’ log to create walls.

In the spring, I like to deepen the lesson by teaching about the Haudenosaunee indigenous peoples, one of the tribes in the area and the original caretakers of our river valley. We talk about the cultures and tell a spooky Haudenosaunee ghost story, and for older students we talk briefly and in an age-appropriate way about the broken treaties made with Europeon colonizers and how that continues to inform our area to this day.

We also visit the Bloomsburg Children’s Museum to explore the long-house style dwelling the Haudenosaunee tribes would have created.

When we return to the woods on our weekly Wednesday in the Woods day, I will instruct students about tree identification as we search for strong and springy yearling birch saplings. Cut a few small twigs, stick the ends in some muddy soil to form an arch. We repeat this to make a series of arches and then will gather fallen bark, ideally birch bark, to create walls and a roof. We might also explore making cordage from natural materials.

This kind of deep examination takes several weeks and builds on each skill, but students are so hungry for this type of learning and play: a short lesson from a grown-up but mostly the students are the leaders. Grown-ups are just a resource to handle the sharp and heavy things.

Some rules with fort building: always be certain of the rules of the property. If you are visiting a state forest, fallen logs and sticks may be used. No living plants may be cut down. Bald Eagle State Forest has several pockets for excellent fort building close to the small town of White Deer. I have also taught fort building in conjunction with James V. Brown Library at the Lycoming Conservation District’s Learning Trail.

Perhaps the biggest hazard to fort building is poison ivy. With climate change, it just seems particularly prominent. A thorough scan of the area is necessary. Look for the infamous mitten-shaped leaves of 3 — which can be green in spring and summer and red and yellow in fall — or the hairy vines that grow up the tree trunks.

Wear waterproof gloves, if sensitive to the plant. Or, bring a water bottle and soap. If you feel you have touched the plant, simply rinse your hands in the cold water for one minute to remove the oil and preventing it from binding to your skin. Then, wash with soap and water for another minute.

Interested in inviting your own child to built fort?

I invite you to remember your own desire to build a secret spot as a child and offer your own child the room to build, to create and to escape. Give them a place to play in natue, and then step back. Trust that they can create on their own. And so they will.

Bethany Marcello is a certified nature teacher and teaches preschool at Fern Hill School in Milton.