The second assessment measurement had students rate their perceptions of their own knowledge and scientific decision-making skills. The instrument was completed in a pre/post test manner by 100 and 79 students, respectively in Fall 2001 in Interdisciplinary Science I (the course utilizing the ESA21 exercises), and was also completed by 169 students in Interdisciplinary Science II at the beginning of the same semester. All of the students in Interdisciplinary Science II had utilized the old laboratory program, allowing us to again compare the ESA21 and conventional exercises. The survey included open-ended and Likert-scale questions, and had six questions regarding content knowledge of basic science, nine questions about content knowledge of environmental issues, five questions about scientific skills, and three open-ended questions about how they view environmental issues. There were noticeable differences in the SCI 1101 pre and post survey results for all of the content and skills questions, with trends towards increased levels of content understanding or awareness of environmental issues in the post-survey. This indicated that the students felt the ESA21 exercises helped to improve their knowledge of the scientific process, basic principles in environmental science, and environmental issues. When the post-survey results (ESA21) were compared to the Interdisciplinary Science II students (old exercises), many of the same trends appeared as in the comparisons of the pre and post-surveys. Students completing the post-survey (ESA21) generally reported higher levels of agreement with statements about increased knowledge and environmental awareness, indicating the ESA21 exercises may have been more successful at improving student perceptions of knowledge than the conventional exercises, perhaps due to the close tie-in with the lecture material and greater relevance to daily life.