Systems Learning With a Conceptual Representation: A Quasi-Experimental Study

• In Event: Supporting Systems Learning 2.0: The Next Phase of Research in Complex Systems in Science Education

Abstract

One challenge for students learning about systems is providing opportunities for them to actually engage with systems phenomena at multiple levels (Jacobsen & Wilensky, 2006). Conceptual representations provide an approach to supporting learning about systems (Hmelo-Silver et al, 2014). One such representation supporting learning and reasoning about ecosystems is the Components-Mechanisms-Phenomena (CMP). CMP supports framing systems thinking around a particular phenomenon or ecological pattern (P); encouraging learners to generate plausible mechanisms (M) that may result in the (P); and explore the components (C) that interact to result in (M and P). CMP guided design in our technology-rich inquiry curriculum. The phenomena provide problems to motivate student learning, for example managing life support in a fish tank, dead and dying fish in a pond, and thinning oyster shells. Curriculum materials provided sources of evidence including graphs and scientific reports along with computer simulations. Simulations provided opportunities for students to engage with mechanisms that underlie the phenomenon. A conceptual modeling tool helped students construct explanatory CMP models.

A quasi-experimental design tested the hypothesis that students in a CMP-guided curriculum would outperform students in typical science instruction with respect to causal mechanisms and connections to phenomena, and micro-level processes.

Participants were seventh grade students. Intervention students (n=65) participated in an eight-week technology-rich ecosystems unit in science class. Comparison students (n=47) participated in business-as-usual science instruction.

Using the Systems and Cycles curriculum and software, students engaged in small group inquiry followed by class discussions about the aquarium, eutrophic ponds, and oceans, and construction of models. The models elaborated ecosystem mechanisms such as photosynthesis, cellular respiration, and decomposition. Three major units of the curriculum focused on (1) an aquarium, (2) a pond, and (3) ocean systems. In each unit, students were introduced to a driving problem and then to drew CMP models (Vattam et al., 2011), study phenomena-oriented hypermedia (Liu & Hmelo-Silver, 2009), and use NetLogo simulations (Wilensky & Reisman, 2006) and revised their models. Students completed pre- and post-tests focusing on ecosystems thinking. We coded tests using a coding scheme derived from Eberbach et al. (2012; Table 1).

Regression analysis demonstrated significant learning gains for the treatment group relative to the comparison for M:M and CMP (Table 2). The effect size (d) was large at 1.35 for M:M and 0.87 for CMP, a moderate-large effect. Qualitative analysis of the drawings showed that the interventions students were more likely to include mechanisms than comparison students.

The intervention was successful aid helping students learn about ecosystems. We conjecture that the CMP intervention encourages students to organize conceptual information using links between mechanisms and the phenomena that served as the problem contexts. The simulations served to as means for students to test ideas while the models helped students to articulate and refine ideas. We need to consider how CMP might be generalized as a tool for teaching systems thinking more broadly. We reiterate Sabelli’s (2006) contention that systems thinking is an imperative for scientifically literate citizens who can reason about the world’s pressing problems.

Authors

• Cindy E. Hmelo-Silver, Indiana University

• Rebecca Jordan, Rutgers University

• Catherine Eberbach, National Science Foundation

• Suparna Sinha, Rutgers University