摘要：AbstractScience teaching should promote more than rote learning, allowing students to be more critical regarding their social circumstances, particularly regarding difficult topics, such as energetic metabolism. In this sense innovative practices are important in science classrooms for motivating and engaging students in science learning. Based on the theoretical and methodological assumptions of educational design research, we engaged in a development study of two prototypes of a teaching sequence in two schools in the state of Bahia, Brazil. The first prototype was implemented and tested in one school, whereas the second was tested in two schools. Our first prototype was based on three design principles. The evaluation of this prototype showed the need to add three additional principles in the second intervention. Using a questionnaire with closed and open-ended questions we were able to evaluate qualitatively and quantitatively both prototypes. Statistical analysis showed a positive effect of the prototypes in both schools. Our qualitative and quantitative data corroborates the following design principles: (i) use of popular science texts; (ii) contextualization with regard to students’ everyday experience; (iii) construction of a cooperative learning process; (iv) survey and work with students’ alternative conceptions; (v) hierarchical approach to different organization levels in living organisms. The sixth principle, focus on written language, did not attain the desirable success, indicating the need of further work concerning this ability.
