"You Live in a Watershed" is a state park exhibit about watersheds. We conducted a two-pronged assessment of learning and attitudes. Study 1 employed a pretest-intervention-posttest design with 30 children visiting the exhibit on a fieldtrip. We found significant increases in knowledge and attitudes. Study 2 was a quasi-experimental comparison of 84 park visitors who interacted with the exhibit or did not. Exhibit visitors demonstrated more knowledge than other Nature Center visitors. Visitors came to the exhibit with strong positive attitudes and beliefs about lakes and water quality, but showed a lack of knowledge about watersheds that the exhibit ameliorated.