This study examines the role of a 6- or 8-week summer university laboratory internship for 56 high ability secondary students in developing the views of these students with respect to the nature of science. Students were assessed using a gender-neutral version of the Test on Understanding Science (TOUS) as part of a pretest-posttest research design. Results indicated no significant change from pretest to posttest on any of the subscales of this test. When all the variables were analyzed, only the internship duration (6-week versus 8-week) showed a significant change. The 8-week group made a significant gain in understanding about the scientific enterprise. The TOUS did not perform well in assessing this population. Although the posttest reliability, measured by KR-20 was a respectable 0.66, the mean difficulty was a high 69.30 and the mean discrimination was only 0.23. These values may be explained by the generally high level of pretest achievement and the overall homogeneity of the students. The accompanying qualitative study indicates that students gained much with respect to understanding the nature of science, but the TOUS is clearly not the best instrument to use in substantiating that finding. (PR)