Lower-secondary introductory chemistry course: a novel approach based on science-education theories, with emphasis on the macroscopic approach, and the delayed meaningful teaching of the concepts of molecule and atom

Abstract

We present a programme for a novel introductory lower-secondary chemistry course (seventh or eighth grade) that aims at the application of theories of science education, and in particular of conceptual/meaningful learning and of teaching methodology that encourages active and inquiry forms of learning The approach is rigorous with careful use of the language, and taking account of students’ alternative ideas and misconceptions. Cognitive development and critical thinking are also taken care of. Experiments are designed to be executed by the students working in pairs. There is connection of science with everyday life and applicat ions and awareness of the environmental problems. Finally, special emphasis is paid to the meaningful introduction of the concepts of molecule and atom; this introduction is delayed until the last two units of the course. The programme is made of six units (matter and soil, water, chemical reactions, air, molecules, atoms) that contain twenty-four lessons. A textbook was written and subjected to a preliminary evaluation by four experienced Greek science teachers, who considered as strong points the following features: emphasis on experimental teaching, observation, description, and explanation of phenomena by the students, taking of students misconceptions into account; in addition, the teachers were enthusiastic about the approach to the concepts of molecule and atom. Finally, the questions of the book were evaluated by using the Pearson, Johnson and Raphael scheme.