The Southeast Alaska Discovery Center is operated by the US Forest Service and serves as one of the best introductions to the Tongass National Forest and the broader Southeast Alaska ecosystem. The exhibits cover the temperate rainforest ecology, the indigenous cultures of the region, the timber and fishing industries, and the landscape of the Inside Passage. Displays are well-funded and genuinely informative rather than perfunctory.
It's a useful first stop in Ketchikan before heading out to Totem Bight or Saxman, and free for children under 15. The building itself, a converted cannery warehouse on the downtown waterfront, is worth a look. The ranger staff can advise on current conditions in the Tongass and Misty Fjords, help plan kayaking trips, and provide trail information.