The aim of this study is to identify the dispositions and opinions of prospective teachers towards critical thinking and to develop primarily their critical thinking dispositions. Pretest-posttest research design was implemented in this study without a control group. The study group was formed with the purposive sampling method. A total of 57 preservice teachers, of whom 26 were males and 31 were females, volunteered for the study. California Critical Thinking Disposition Scale was used for data collection and semi-structured interview form was used to obtain the qualitative data. The overall critical thinking dispositions pre-test scores of the students as well as the scores they have obtained in the sub-dimensions of analyticalness, open mindedness, inquisitiveness, and systematicness revealed that they had moderate dispositions in these sub-dimensions, whereas the scores they obtained in the sub-dimensions of self-confidence and truth-seeking revealed that they had low critical thinking dispositions in the respective sub-dimensions. The overall critical thinking dispositions post-test scores of the students obtained after the experimental procedure indicated a moderate disposition, as it was revealed by the overall pre-test scores, with the exceptions of the sub-dimensions of self-confidence and truth-seeking, in which the students' scores increased from low to moderate. All in all, a significant difference was found between the mean pretest and posttest scores. It was determined that when encountered an event or a problem that the participants took cognizance of subjects such as paying attention to the data available and unavailable, being attentive to seeking evidence, developing empathy, making reasonable conclusions, and making judgments through creating criteria when making decisions. These results have indicated that the education provided contributes positively to critical thinking and to the critical thinking disposition.