TEACHING UPPER-SECONDARY STUDENTS ABOUT CONSERVATION OF MECHANICAL ENERGY: TWO VARIANTS OF THE SYSTEM APPROACH TO ENERGY ANALYSIS

Conventional teaching about the law of conservation mechanical energy (LCME) often results with students trying to solve problems by remembering similar they already covered in classes. Consequently, many fail transfer their knowledge simplest real-life problems. Therefore, a pre-test – post-test quasi-experiment was conducted evaluate effects an alternative, system-based approach LCME. The study included 70 upper-secondary from First Bosniak Gymnasium Sarajevo, Bosnia and Herzegovina. Firstly, all learned conventional way. Then wrote test on LCME had three additional hours this topic, where one group line forces-variant system (e.g., discussing conservative non-conservative forces) other process-variant same system’s states processes like thermodynamics). For both variants, only proved substantially improve students’ level understanding compared after teaching. It follows that may work well at level, if it is introduced through scaffolding-and-fading technique. Keywords: quasi-experiment, energy, materials, strategies