There's a lot to learn in the Fisher Museum, and teachers seem to know it.

Museum Coordinator John O'Keefe estimates that between 50 and 75 groups visit every year. "We get everything from elementary schools, Cub Scouts, secondary schools, through universities and senior groups." For many groups, O'Keefe gives a guided tour, starting with a video presentation, which presents an overview of the history of Harvard Forest, from its origins as a demonstration forest for silvicultural techniques to its current role as one of the National Science Foundation's Long Term Ecological Research Sites. The groups then tour the models.

"The more I interact with groups, the more information comes out," says O'Keefe. Depending on the season and weather, they finish with a walk in the Forest to look at what they've learned about.

Visitors also arrive on their own. "Many people have heard about it either by word of mouth, or through the forestry and natural history communities, so they make a point of visiting when they're in the area," says O'Keefe. A glance at the guestbook reveals people from as close as Petersham and as far as Austria. At the entrance, visitors can pick up guides, maps of the Forest, and a scavenger hunt -- a list of details to look for in the models, like a rabbit, a measuring tape, and a lunch box. In the center of the room, visitors can watch a video presentation on Northeastern forests. The topic changes monthly, ranging from the dangers of the hemlock woolly adelgid (a conifer-killing insect) to hemlock forests to ice harvesting in New England.

The Fisher Museum is open weekdays from 9 a.m. to 5 p.m., year- round. A staff of well-informed docents keeps the Museum open on weekends between May and October, from noon to 4 p.m. Admission is free. Arrangements for large groups can be made by calling: (978) 724-3302. The Harvard Forest is located on Route 32 in Petersham, Mass. Directions can be found on the Forest's Website http://lternet.lternet.edu/hfr/.