Title: Relationships between Conceptual Knowledge and Reasoning about Systems
Description: Reasoning about systems is necessary for understanding many modern issues that face society and is important for future scientists and all citizens. Systems thinking may allow students to make connections and identify common themes between seemingly different situations and phenomena, and is relevant to the focus on cross-cutting concepts in science emphasized in the Framework for K-12 Science Education Standards (NRC, 2011) and Next Generation Science Standards (Achieve, 2013). At the same time, there is emerging empirical and theoretical support in science education for fostering the development of science reasoning alongside content understanding, as opposed to the perspective that reasoning occurs after a certain threshold of content mastery has been achieved. However, existing research on systems thinking has treated this reasoning as a set of universal skills and neglected the role of content, or has conceptualized a progression in which content mastery precedes systems reasoning without consideration of rudimentary forms of reasoning.

This study focused on describing individual variations in the ways that 8th and 9th grade students reason about changes in a system over time to identify characteristics of systems and pre-systems thinking and to investigate the relationship between this reasoning and the students' application of content. This study found a generally linear relationship between content and reasoning, with interesting deviations from this trend among students who demonstrated at least a moderate level of content understanding but had not yet achieved mastery. Four profiles of this relationship emerged which warrant different instructional support. Implications are presented for science educators and developers of curricula and assessments. This includes recommendations for learning objectives, the design of written curriculum materials, and the development of assessments that aim to promote and measure reasoning about systems in science.