Teaching students about the nature of science is an important and necessary part of secondary science curricula. The Utah State Office of Education has provided specific guidelines called intended learning outcomes (ILOs) to teachers in the state. The ILOs are based on the national standards presented in the Project 2061 publications of the American Association for the Advancement of Science in 1990 and 1993. The ILOs are not tied to any one scientific discipline such as biology or chemistry, but are intended as global statements describing what scientists do and how scientific knowledge is gained. ILO 6 prescribes that students be taught about the nature of scientific inquiry and the nature of the resulting knowledge claims. State education officials currently assess knowledge of the ILOs through items which are embedded in content-specific, multiple-choice items. This practice confounds knowledge of the nature of science with the content knowledge from a particular course. This project describes the development of an instrument to assess high school students' knowledge of the nature of science separate from their knowledge of any particular scientific discipline. The resulting questionnaire largely meets its intended goal, but still needs improvement. The current questionnaire has 24 items with an internal consistency reliability estimate of .74. Students participating in the pilot administration may have exhibited some apathy which may have affected the reliability estimate obtained from their responses. Factors such as this may help explain the low internal consistency reliability estimate of this questionnaire and will make the validity of the questionnaire difficult to demonstrate. In spite of this and other shortcomings, the questionnaire may still be useful to secondary science teachers to gain an understanding of their students' knowledge about the nature of science. Based on this knowledge, teachers may be able to design specific instruction to teach students correct knowledge about the nature of science. Since internal consistency reliability estimates are low, the validity of this questionnaire is tenuous. Therefore, caution should be exercised in making judgments about students that would affect measures of academic performance.