This study aims to develop a new cooperative learning technique and to examine the effectiveness of this technique. In the study, action research pattern, in which one of the qualitative research methods was used. The study included 12 male and 8 female students, in total 20 students, studying at 5th grade of a secondary school in Van province of Turkey in second semester of 2015-2016 academic year. The study was conducted for 4 times a week over the course of 8 weeks in "Let's Meet the World of Living Creatures", "A Must of our Lives: Electric" and "The Mystery of Earth" units of science class. This study consisted of three phases. The first draft form of the "question jury" technique was formed as a result of the literature research at the first stage. At the second stage, "question jury" draft form was applied to the mentioned group for 4 weeks and the "question jury" application was put into its final form in the light of the obtained data. The developed "question jury" was applied to the same group for 4 weeks at the third stage. The data in the study were collected using semi-structured interview form, observation forms, student diaries, video recordings and "information card form". Content and descriptive analysis methods were used to analyze the data. As a result of the analyses, "cognitive learning", "affective learning", "assessment" and "process" themes and various codes under these themes were formed. As a result; it was determined that, this technique developed was in accordance with the principles of cooperative learning, it increased students' conceptual levels, students found the technique useful, simple and understandable, this application led them to study the course and to research the knowledge, the students enjoyed the participation and they helped students to make self-assessment and contributed to their personal development.