Using Content Knowledge for Teaching Science Assessments to Examine Elementary Science Teachers' Practice-Based Knowledge

• In Event: Developing and Validating Indicators for Teachers' Science and Mathematics Content Knowledge for Teaching

Abstract

One of the “grand challenges” facing science educators today is a lack of understanding of the mechanisms through which different learning opportunities are more or less effective for science teachers (Wilson, 2013). A key reason for this lack of understanding is that the field does not have valid and reliable assessments of science teachers’ knowledge that can be used to make decisions about which professional learning opportunities are most beneficial (Minner, Martinez, & Freeman, 2012). In this study, empirical evidence from cognitive interviews are used to examine how two types of science measures -- practice-based content knowledge for teaching (CKT) items and subject matter knowledge items – assess distinct aspects of elementary teacher’s knowledge.

Researchers have theorized CKT to comprise a number of content domains, such as the subject matter knowledge that most literate adults hold, specialized forms of content knowledge that are only used in teaching practice, and pedagogical content knowledge (Author, 2008; Hill, Ball, & Shilling, 2008; Hill et al., 2004; Magnusson, Krajcik, & Borko; 1999; Park & Oliver, 2008; Author, 2009). In this conceptualization, the latter two domains include knowledge that is “tailored to the work that teachers do with curriculum, instruction, and students” (Ball, Hill, & Bass, 2005, p. 16), such as anticipating and interpreting students’ ideas, constructing explanations, and selecting and modifying resources for instruction. The evidentiary base for the importance of science teachers’ practice-based knowledge suggests that the field could benefit from measures that go beyond merely assessing their subject matter knowledge.

In this study, 30 upper elementary science teachers participated in cognitive interviews using concurrent think aloud methodology (Ericsson & Simon, 1984) to investigate how the knowledge and reasoning science teachers draw upon compares across item types (practice-based CKT items and subject matter knowledge items). Analysis focused on comparing teachers’ answer choices and their justifications of their selections to the intended function of each item. To do so, we compared teachers’ responses to task design rationales, which specify the knowledge that each item is intended to measure and the ways in which teachers are expected to reason through each item (Author, 2013b). Findings revealed that the majority of teacher’s think aloud responses on the practice-based CKT items were coded for confirmatory evidence showing that these items required them to apply their content knowledge to specific tasks of teaching. In particular, we found that teachers leveraged their knowledge of curriculum, instruction, and students, in addition to their knowledge about the subject matter, to support them in defining the critical elements in each teaching scenario and reasoning through the options in each item. In contrast, it was rare for teachers to use their practice-based knowledge to select their answers to the subject matter knowledge items. Overall, findings provide empirical evidence to validate the underlying theoretical argument that the nature of the knowledge used in teaching science goes beyond formal subject matter knowledge.

Authors

• Jamie N. Mikeska, Educational Testing Service

• Geoffrey C. Phelps, Educational Testing Service