Introduction: Here we report the results obtained in an innovative teaching experience that encourages the development of Critical Thinking skills through motivational intervention. Understanding Critical Thinking as a theory of action, "we think to solve problems", and accompanying this concept with a program aimed at teaching/learning Critical Thinking and with active methodologies such as "Problem-Based Learning" (PBL), we developed a parallel program designed to foster motivation for the development of these skills. This motivational instruction is based on a theoretical option that understands motivation as the result of two variables: "Expectancy/Value." These two concepts enable an intervention in motivation towards more efficient Critical Thinking. Method: 89 Spanish university students of both sexes were enrolled in the study, with ages between 20 and 30 years, who were assessed by means of the PENCRISAL and the AGQ at both the start and the end of the intervention, together with continuous assessment. During the intervention, all the students received instruction in Critical Thinking. However, only half of the sample also participated in the motivation program. Results: The results show that instruction in Critical Thinking skills through ARDESOS was successful. Moreover, the results obtained concerning motivation pointed to a maintenance of the scores in the group subjected to the motivation program. Discussion: The results of the present study show that to a large extent intervention in motivation functions well. Nevertheless, it is necessary to increase such improvements. Thus, we describe a tool for studying the motivational factors of Critical Thinking, which could be especially useful from the perspective of instruction and pedagogical research.