Scaffolding children's understanding of the fit between organisms and their environment in the context of the practices of science

This research project applies the learning progression perspective to the teaching of the conceptual underpinnings of evolution for 2nd and 3rd graders. We frame the progression from the epistemic perspective that understanding a scientific idea encompasses using that idea, in prediction, interpretation and explanation of the natural world. The progression foregrounds the question of the fit between organisms and their environment. This paper reports on the first step of the project, our teaching of the curriculum in an urban summer school and the analysis thereof. We analyze students' reasoning during prototype instructional activities and in comparison of pre -and post-interviews. We have had success scaffolding children's understanding of differential survival advantage of different traits. While we have existence proofs of children coming to understand the impact of this differential on changing distributions across generations, this next step of understanding appears to be much more difficult.