Hayat Hokayem

A Learning Progression for Feedback Loop Reasoning at Lower Elementary Level

This study examines to what extent elementary students use feedback loop reasoning, a key component of systems thinking, to reason about interactions among organisms in ecosystems. We conducted clinical interviews with 44 elementary students (1st through 4th grades). We asked students to explain how populations change in two contexts: a sustainable ecosystem and an ecosystem that is missing predators. We used an iterative process to develop a learning progression for feedback loop reasoning, and used the learning progression to code interview episodes. The study produces three findings. First, very few students recognised the cyclical relationships among populations in a sustainable ecosystem (Level 7). Second, very few students identified both reproduction and food as the factors affecting population in a context missing predators (Level 4). Finally, students’ reasoning was inconsistent across the two contexts. We also discuss the implication of these findings for teaching and learning of food webs at elementary school.

Relating ecological technical terms to students’ reasoning between 1st and 4th grades

Abstract This study investigates how lower elementary students used the technical terms in the context of ecology. We interviewed 44 students using several scenarios related to the ecosystem. We determined the general frequency of technical terms used from a preselected list commonly employed by scientists in their discourse about ecosystems. Then, we identified the contextualisation of the technical terms. The results showed three categories: naming – where the terms referred to an event or object without any appropriate scientific explanation, partial explanation – where the terms revealed a scientific idea mixed with other alternative conceptions, and complete scientific explanation – where the terms were used to completely convey the proper scientific idea. We discuss the practical implication of those results for teaching ecology.