• , Rose-Hulman Institute of Technology
• , Pennsylvania State University
• , United States Air Force Academy
• , Pennsylvania State University
• , Cornell University
• , Arizona State University

The Dynamics Concept Inventory (DCI) team developed a concept inventory for sophomore-level dynamics. Dynamics is generally taken by mechanics, aerospace, civil, and industrial engineers, and the prerequisite is usually statics and two semesters of calculus. The efforts of this team are focused on the second half of the dynamics course, that is, rigid-body dynamics, since the Force Concept Inventory (FCI) sufficiently covers particle dynamics. The DCI team grew out a meeting held in San Antonio, Texas, in September 2002. This meeting, attended by fourteen mechanics faculty members from an equal number of universities, was instrumental in encouraging work on a DCI and on reinvigorating the work on the Strength of Materials Concept Inventory. For more information on the development of the DCI, please contact , Arizona State University, leader; , Pennsylvania State University; , Rose-Hulman Institute of Technology; , Pennsylvania State University, and , U. S. Air Force Academy. This team has worked closely together since the San Antonio meeting to assemble a concept inventory that addresses the commonly held alternate conceptions in rigid-body mechanics. Later, (Cornell) joined the group.

Knowledge of student learning has expanded in the last fifteen years but remains unfamiliar to most science and engineering instructors. Research literature on student learning has yet to widely influence either textbook presentations or classroom pedagogy. Teaching of engineering subjects continues to be patterned after how instructors were taught when they were students, rather than being informed by research on learning. A hindrance to reform in science, technology, engineering, and mathematics (STEM) education has been the absence of assessment instruments that can measure the value added to student learning by new ways of teaching important material.

The Foundation Coalition and others have been working on the development of concept inventory (CI) assessment instruments patterned after the Force Concept Inventory (FCI) instrument of Hestenes, Wells, and Swackhamer (for revised edition, see <http://modeling.la.asu.edu/R&E/Research.html>). Concept inventories are multiple-choice tests in which incorrect answers are carefully constructed from research on common student misconceptions of the concept(s) involved. Such assessment inventories can play an important part in relating teaching techniques to student learning. Coalition work began three years ago on CIs for thermodynamics, solid mechanics, signals and processing, and electromagnetics. Two years ago work got under way on CIs for circuits, fluid mechanics, engineering materials, transport processes, and statistics. This past year work began on chemistry, computer engineering, dynamics, electronics, and heat transfer CIs.

Members of this group had many conferences and communication, as they put together a CI instrument. Below is the chronology of their accomplishments:

• Used 25 participants in a Delphi process to define concepts covered in rigid-body dynamics and to determine this group’s perceptions about how well students understand these concepts;
• Composed questions that involved these concepts;
• Used these questions with focus groups of students who had recently taken dynamics, to elicit student responses;
• Built sets of multiple-choice answers to these questions, based on the elicited student responses;
• Tested and refined questions and answers, using focus student groups;
• Composed version 1 of a dynamics concept inventory, which is ready to test fall 2003 in some dynamics classes.

Focus groups uncovered student misconceptions about dynamics concepts—misconceptions that persisted through and beyond instruction. As an example, the misconceptions about one of the fundamental concepts of rigid-body mechanics is included in the sidebar. Every student except one in the focus groups at three universities chose the wrong answer to this problem. The most common incorrect answer was that the object moves upward to the right and begins to rotate. The equations developed in rigid-body mechanics show that the object actually moves to the right (in the direction of the applied force) and begins to rotate about the center of mass. Focus group results show that students have not connected what the equations foretell and what students think will happen in reality. The one student who chose the correct answer did so because he experimentally observed the behavior with a sheet of paper on his desk—a behavior he did not anticipate.

The box of mass m shown is initially at rest on a smooth, frictionless, horizontal table. The box is acted upon by a constant force F as shown. The line of action of F is located a distance h from the center of mass of the box, G. Describe the path of the mass center of the box and how the orientation of the box will change.

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At the Concept Developers Meeting held at Frontiers in Education Conference 2002 in Boston, the DCI team agreed to use the Delphi process, patterned after that used for the concept inventory team at Colorado School of Mines [1,2,3] to determine a list of the important concepts, as well as misconceptions, in dynamics. They began the process by recruiting 25 seasoned faculty members from diverse institutions, ranging from community colleges to research universities, and including minority and women faculty. These faculty members described those concepts in rigid-body dynamics that their students have difficulty understanding. The team told the Delphi participants to focus on areas in which students often display insufficient conceptual understanding rather than focusing on student difficulties with analysis skills. Once the raw data were collected from the Delphi participants, these were categorized and summarized; final statements for each of the 24 important concepts (and alternate misconceptions) were developed. In round two of the Delphi process, each of the participants estimated the proportion of their students who understand the issue or concept at an acceptable level at the end of dynamics and described how important they believe it is for students to understand the concept. From the collected data, the team has identified eleven concepts from rigid-body dynamics that should be covered on the DCI. Student focus groups have also been used to address alternate conceptions that involve the concepts identified by the Delphi process.

The work accomplished in the first half of 2003 was reported at the 2003 ASEE Annual Conference in Nashville, TN [4]. This paper won best of session in the Mechanics Division. An update is available in a paper for the 2005 ASEE Annual Conference in Portland, OR [6].