SARATOGA SPRINGS, N.Y.  Fat, cold droplets splashed from the sky as the students struggled into their uniforms: rain pants, boots, mittens and hats. Once buttoned and bundled, they scattered toward favorite spaces: a crab apple tree made for climbing, a cluster of bushes forming a secret nook under a willow tree, a sandbox growing muddier by the minute.

They planted garlic bulbs, discovered a worm. The rain continued to fall. It was 8:30 a.m. on a recent Wednesday, and the Waldorf School’s “forest kindergarten” was officially in session.

Schools around the country have been planting gardens and planning ever more elaborate field trips in hopes of reconnecting children with nature. The forest kindergarten at the Waldorf School of Saratoga Springs is one of a handful in the United States that are taking that concept to another level: its 23 pupils, ages 3 ½ to 6, spend three hours each day outside regardless of the weather. This in a place where winter is marked by snowdrifts and temperatures that regularly dip below freezing.

The new forest kindergarten, which opened here in September, is an extreme version of the outdoor learning taught at more than 100 Waldorf schools, all but a handful of them private, scattered throughout the United States. They are based on the teachings of the Austrian philosopher Rudolf Steiner and emphasize the arts and the natural world, with no formal academic curriculum until first grade.