Exploring Undergraduates' Understanding of Photosynthesis Using Diagnostic Question Clusters

Abstract

We present a diagnostic question cluster (DQC) that assesses undergraduates' thinking about photosynthesis. This assessment tool is not designed to identify individual misconceptions. Rather, it is focused on students' abilities to apply basic concepts about photosynthesis by reasoning with a coordinated set of practices based on a few scientific principles: conservation of matter, conservation of energy, and the hierarchical nature of biological systems. Data on students' responses to the cluster items and uses of some of the questions in multiple-choice, multiple-true/false, and essay formats are compared. A cross-over study indicates that the multiple-true/false format shows promise as a machine-gradable format that identifies students who have a mixture of accurate and inaccurate ideas. In addition, interviews with students about their choices on three multiple-choice questions reveal the fragility of students' understanding. Collectively, the data show that many undergraduates lack both a basic understanding of the role of photosynthesis in plant metabolism and the ability to reason with scientific principles when learning new content. Implications for instruction are discussed.

How Can We Improve Problem Solving in Undergraduate Biology? Applying Lessons from 30 Years of Physics Education Research

“…Not all concept inventories have been developed with attention to evidence of validity and reliability (Huffman and Heller, 1995), and few directly measure problem-solving or critical-thinking skills (Smith and Tanner, 2010), as also described above. Nonetheless, several of the most recently developed biology concept inventories/assessments have demonstrated utility in uncovering concepts for which students have persistent difficulties (Garvin-Doxas and Klymkowsky, 2008; Parker et al ., 2012; Smith and Knight, 2012). In addition, several recently developed assessments are devoted at least in part to specifically measuring problem solving (i.e., diagnostic question clusters [DQC]; Parker et al ., 2012), critical thinking (Bissell and Lemons, 2006), and basic process skills (Gormally et al ., 2012).…”

“…Nonetheless, several of the most recently developed biology concept inventories/assessments have demonstrated utility in uncovering concepts for which students have persistent difficulties (Garvin-Doxas and Klymkowsky, 2008; Parker et al ., 2012; Smith and Knight, 2012). In addition, several recently developed assessments are devoted at least in part to specifically measuring problem solving (i.e., diagnostic question clusters [DQC]; Parker et al ., 2012), critical thinking (Bissell and Lemons, 2006), and basic process skills (Gormally et al ., 2012). In fact, assessing how students engage in scientific practices is important to all DBER communities (NRC, 2012a).…”

“…DQCs (Parker et al ., 2012) and Bissell and Lemons' (2006) methods are encouraging steps toward establishing and exploring these links. Work that explores the kinds of links between conceptual knowledge and sense making with actual problem solving competence should also focus on developing assessments that are validated and easy to deploy.…”

Learning Progressions & Climate Change

“…It [glucose] is made of C 6 H 12 O 6 and so it needs the CO 2 to make for the carbon and it has water that uses H for the water from the water, too (Parker et al, 2012). Although he could not immediately generate an answer, he realized that he needed to account for each of the elements in the glucose that was produced by photosynthesis.…”

“…Longitudinal studies were used to see whether individual students actually progressed through the designated levels. We have done parallel work with undergraduates in introductory biology courses using interviews, essay questions, and forced-choice questions (Wilson et al, 2006;Richmond et al, 2010;Parker et al, 2012).…”