The inquiry approach to teaching science is now being used at the college level, principally in physical science courses for the general student not majoring in science. Science courses for the general student can contribute to the level of scientific literacy in society, particularly if ability to use scientific inquiry is considered an important component of scientific literacy. For this study, it was assumed that favorable attitudes toward inquiry might lead to greater utilization of scientific inquiry by students as members of society. In the inquiry method of teaching, the student is to learn from experiences with simple laboratory experiments. There are several approaches to the use of inquiry, but the most popular form involves the basic processes of 1) observing phenomena, 2) obtaining and comparing measurements on phenomena, 3) drawing conclusions or inferences from the observations, and 4) recognizing some of the assumptions underlying the conclusions. This form is called "guided discovery;" other forms might be more rigorous or more historical in approach. In the guided discovery method used in the physical science course on which this study was made, the students followed a prepared sequence of laboratory investigations, the results of which were left open-ended. Scientific methods of inquiry were used more as a learning method than as a rigorous approximation to science. The attitudinal effects of inquiry teaching might have been particular to the specific form of inquiry used. The inquiry course studied was not intentionally designed to change attitudes, yet some attitudinal effect is to be expected from any course or method of teaching. The main question of the study was whether any attitudinal effects of inquiry teaching could be demonstrated. No known previous study of physical science courses, with or without inquiry, covered all three of these elements in this study: the science course was at the college level, the course used inquiry, and attitudes toward inquiry or scientific methods were investigated rather than general attitudes toward science. To avoid problems of finding another population with which to compare changes in attitude, an internal criterion for attitude change was used. The basic design of the study made use of the fact that the physical science course studied came as a two-semester sequence. The student decision whether or not to take the second semester of the inquiry course was taken as a behavioral manifestation of student attitude toward the first inquiry course. This unobtrusive measure of attitude was compared to attitude changes within the first course and to other possibly relevant variables. Multivariate linear regression analysis was used to find which variables predicted the decision to take a second inquiry course. Commonality analysis was included to separate the independent from the joint effects of the variables