MacKenzie R. Stetzer

Improving the preparation of K-12 teachers through physics education research

Physics education research can contribute to efforts by college and university faculty to improve the preparation of K-12 teachers to teach physics and physical science. Examples from topics included in precollege and university curricula are used to demonstrate the need to help K-12 teachers deepen their understanding of basic physics, to illustrate how research-based instructional materials can assist in this process, and to examine the impact on student learning in K-12 classrooms.

A Campus-Wide Study of STEM Courses: New Perspectives on Teaching Practices and Perceptions

Teachers observed 51 university-level science, technology, engineering, and mathematics (STEM) courses and collected information on the active-engagement nature of instruction. These results give a comprehensive view of the diversity of STEM instruction and student in-class behavior at a campus-wide level. The authors discuss how these results could be used to design targeted professional development.

New insights into student understanding of complete circuits and the conservation of current

The research reported in this paper represents an in-depth examination of the finding from an earlier investigation that university students often do not develop a functional understanding of the concept of a complete circuit. Participants in this study included undergraduates in introductory and upper-division physics courses as well as graduate teaching assistants. Although the concept of a complete circuit is covered in the standard undergraduate curriculum, students in all three groups had difficulty in applying this concept to single-loop, resistive circuits. Students frequently did not apply the conservation of current when analyzing circuits containing more than one battery. Certain basic conceptual difficulties spanned all of the populations and even persisted after instruction in upper-division courses that involved analog electronics.

Student understanding of wave behavior at a boundary: The relationships among wavelength, propagation speed, and frequency

This paper reports on the second part of an investigation of student understanding of wave behavior. A previous paper focused on the reflection of pulses from fixed and free ends. In this paper the focus is on the more complicated behavior of periodic waves at a boundary between two different media. We identified several erroneous reasoning approaches. Many students treated the relationship ν = λf as a mathematical identity, and did not recognize how the variables wavelength, frequency, and propagation speed can be manipulated experimentally. Many difficulties do not appear to be limited to the context of refraction of waves at a boundary, but seem to hinder student understanding of more advanced physics phenomena such as interference and diffraction.

A Campus-Wide Investigation of Clicker Implementation: The Status of Peer Discussion in STEM Classes

The authors observed university STEM classes and documented clicker use. Comparisons of classes taught with and without clickers show that the use of clickers does not significantly impact lecture time. One explanation stems from the observation of three distinct modes of clicker use that differ in instructional behaviors and question difficulty.

Student understanding of wave behavior at a boundary: The limiting case of reflection at fixed and free ends

We investigated student understanding of wave behavior at a boundary in the context of pulses and periodic waves in water and in elastic media. The participants were science and engineering majors in introductory calculus-based physics. We document several conceptual and reasoning difficulties and describe the refinement and assessment of our instructional materials. The results show significant improvements in student learning of some aspects of superposition and reflection, but some reasoning patterns that yield incorrect predictions persist. Among these difficulties is the tendency to employ simple rule-based approaches in cases in which a systematic application of the superposition principle is necessary to predict the motion of points in the medium over an interval of time.

Helping Preservice Teachers Implement and Assess Research‐based Instruction in K‐12 Classrooms

The Physics Education Group at the University of Washington offers special physics courses for preservice teachers. The three‐quarter sequence helps prospective teachers develop an in‐depth understanding of some of the important basic concepts they will teach. The guided‐inquiry pedagogical approach provides them with an opportunity to learn as they will be expected to teach. As a result of the course, preservice teachers also come to recognize some conceptual and reasoning difficulties commonly encountered by students. A culmination of their experience is a teaching practicum in which the preservice teachers apply what they have learned to instruction in middle or high school classrooms. Observations of the preservice teachers as they design, teach, and assess their lessons contribute to our understanding of the type of preparation needed for them to be able to teach physics and physical science by inquiry.

Investigating the role of model-based reasoning while troubleshooting an electric circuit

We explore the overlap of two nationally-recognized learning outcomes for physics lab courses, namely, the ability to model experimental systems and the ability to troubleshoot a malfunctioning apparatus. Modeling and troubleshooting are both nonlinear, recursive processes that involve using models to inform revisions to an apparatus. To probe the overlap of modeling and troubleshooting, we collected audiovisual data from think-aloud activities in which eight pairs of students from two institutions attempted to diagnose and repair a malfunctioning electrical circuit. We characterize the cognitive tasks and model-based reasoning that students employed during this activity. In doing so, we demonstrate that troubleshooting engages students in the core scientific practice of modeling.

Investigating student understanding of operational-amplifier circuits

The research reported in this article represents a systematic, multi-year investigation of student understanding of the behavior of basic operational-amplifier (op-amp) circuits. The participants in this study were undergraduates enrolled in upper-division physics courses on analog electronics at three different institutions, as well as undergraduates in introductory and upper-division electrical engineering courses at one of the institutions. The findings indicate that many students complete these courses without developing a functional understanding of the behavior of op-amp circuits. This article describes the most prevalent conceptual and reasoning difficulties identified (typically after lecture and hands-on laboratory experience) as well as several implications for electronics instruction that have emerged from this investigation.

Investigating student ability to apply basic electrostatics concepts to conductors

In teaching electrostatics and electric circuits, it is necessary to introduce abstract ideas such as electric fields and electric potential before discussions of circuits can take place. The Physics Education Group at the University of Washington has found that students in introductory courses can build a functional understanding of some aspects of electric fields and potential, but their understanding of these concepts appears to falter when applied to systems involving conductors. Some specific examples will be discussed. The results will be used to inform the further development of tutorials in electrostatics.