Abstract: The authors explored the influences of 3- and 5-day residential environmental education programs at the Great Smoky Mountains Institute at Tremont (TN) on participants' connections with nature, environmental stewardship, interest in learning and discovery, and awareness of the Great Smoky Mountains National Park and biodiversity. The authors found significant positive, short-term effects on all outcomes of interest. Also, 3-month delayed posttests indicated retention of significant gains in environmental stewardship and awareness, whereas other gains faded. Longer stays and active engagement of visiting teachers in on-site instruction enhanced most outcomes. The authors discuss the influences of previsit preparation and group size on participants.