Fifth-graders from Montgomery Elementary School convened in a classroom “as big as all outdoors” on Tuesday, visiting the Schneebeli Earth Science Center for an environmentally themed field trip timed to this month’s Earth Day observance. As they have for a number of years, forest technology students at Penn College (marshaled by Dennis F. Ringling, professor of forestry) staffed a dozen stations to educate rotating groups of pupils on a variety of woodland topics.