Most state and national parks offer educational programs. Sign up for mailing lists and activity notices.
Museums make great field trips, as do local businesses.
A group trip to a nearby apple orchard taught us every aspect of managing an orchard. We saw trees being grafted to produce different apple varieties, watched apples being made into cider, and tasted the juice. Groups Learning with a chosen group is a great benefit of homeschooling. Last year we were part of a homeschool medieval group. Parents took turns helping with crafts, telling stories, and planning a big May Day festival, complete with costumes and a feast.