For close to 30 Hyde Park preschool children, a recent trip to the Arnold Arboretum, the majestic 265-acre botanical garden run by Harvard University in Jamaica Plain, meant a journey to a world alive with natural wonders and surprises.

In a grove of horse chestnut and buckeye trees flooded with late afternoon sunlight and autumn’s shades of ginger and honey, the eager 3-, 4- and 5-year-olds filed off a bus and paired with volunteer guides from the arboretum. Together they explored their colorful environment, examining the leaves on the trees, inspecting their trunks, and carefully studying the fallen chestnuts that littered the ground.

“Somebody ate lunch and we can see the results of it,” said volunteer Barb Balasa to her two young companions, Xavier and Alianna, as she showed them a partially chewed chestnut. “Those are the teeth marks of the squirrel or the chipmunk,” she explained.

Education has always been a vital part of the arboretum, which was founded in 1872 with a grant from the trustees of New Bedford whaling merchant James Arnold, who gave a portion of his trust to Harvard College to create the arboretum in his name.

The curious students were part of the arboretum’s Field Study Experiences, which introduces kids to the plant life in its vast meadows and woodlands. Since 2004, the arboretum has worked with local chapters of Head Start, a national program that assists children from low-income families by providing a variety of child development services. Initially, the arboretum simply funded a bus to bring the young explorers to the grounds with their teachers and parent chaperones, but organizers soon realized something was missing.

“What we found was that the teachers were not really comfortable here; they wanted somebody to help them get acquainted with the [place],” said Nancy Sableski, manager of children’s education at the arboretum.

She began pairing the students, parents, and teachers with adult volunteers who could talk to them about the area and lead them on guided tours. In 2007, with help from a private grant, the program was expanded further to include a pilot program tailored specifically to the needs of the preschoolers.

“We wanted to introduce the youngest children in Boston to the arboretum for several reasons,” said Sableski “Initially, I hoped to provide a safe outdoor resource to low-income children in Boston who might not otherwise come here. We also wanted to attract families that live near the arboretum. Since parents come as chaperones, we knew that this was a way to introduce them to the arboretum.”

In addition, Sableski said she realized the program offered the opportunity to begin science education with preschoolers.

With the help of Cindy Hoisington, a former teacher at South Side Head Start who now works for the Educational Development Center Inc. (EDC), a nonprofit based in Newton, Mass., they developed a focused curriculum.

For the new program, the children make three trips to the horse chestnut and buckeye grove, visiting it in the spring, summer, and fall to study the changes in the trees throughout the different seasons. In addition, Hoisington helped create a group of training sessions for teachers and lesson plans based on the students’ field trips that they could use back in their classrooms.

According to Hoisington, the cumulative effect of the children’s visits is an important part of the program’s success.

“It’s the three trips that is the key,” she said, “they really learn by connecting different experiences.”

She also praised the ability of the adult volunteers to connect with their young visitors.

“When you have adults that are really tuned into the kids’ level … you get their engagement and enthusiasm about the environment,” she said. “It’s through the engagement that the learning is increased.”

Another objective of the program is to help children feel comfortable and safe in the natural world. For some, the field visits represent their first experience in a rustic setting, and can be a little frightening.

“The perception of danger is remarkable,” said Sableski, as she recounted the students’ fears of snakes, spiders, and giant rabbits. “Starting them out [here] as early as possible can only see benefits.”

Back at the grove, as the children prepared for the bus for the trip home, they showed off their extensive collections of leaves and horse chestnuts and their colorful, if not exactly accurate, artwork.

“That’s a blue leaf,” said one little girl, pointing to her picture and smiling proudly.

“It’s a good way for them to experience nature,” said LaToya Cromartie, lead teacher at South Side Head Start as she helped usher the students back on the bus. “They love the outdoors. … They love picking up and looking at objects. It’s good for them; they see every little bug and every little thing. It’s a good way for them to experience nature.”

Sableski said she hopes to continue the program and possibly look at developing it as a model for similar organizations nationwide.

“My hope,” she said, “is that we sit down with [EDC] and talk about what we’re starting [here] as a model that could be recreated in arboretums and botanical gardens across the country.”

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