Commentaries regarding appropriate methods for researching professional development have been a frequent topic in recent issues of Educational Researcher as well as other venues. In this article, the authors extend this discussion by observing that randomized trials of specific professional development programs have not enhanced our knowledge of effective program characteristics, leaving practitioners without guidance with regard to best practices. In response, the authors propose that scholars should execute more rigorous comparisons of professional development designs at the initial stages of program development and use information derived from these studies to build a professional knowledge base. The authors illustrate with examples of both a proposed study and reviews of evidence on key questions in the literature.

Although video cases and video clubs have become popular forms of teacher professional development, there have been few systematic investigations of designs for such programs. Programs may vary according to (a) whether teachers watch videos of their own/their peers’ instruction, or whether teachers watch stock video of unknown teachers; and (b) whether discussions are led by trained facilitators or by participants themselves. Using a factorial design, we defined four treatment conditions based on these possibilities, then assigned three groups of teachers to each condition. Teachers watched, scored, and discussed mathematics instruction according to each treatment condition’s protocol. Evidence from groups’ conversations and teachers’ video analyses and lesson reflections suggest that the teacher-led, own-video condition is slightly superior to the other conditions.

Measurement scholars have recently constructed validity arguments in support of a variety of educational assessments, including classroom observation instruments. In this article, we note that users must examine the robustness of validity arguments to variation in the implementation of these instruments. We illustrate how such an analysis might be used to assess a validity argument constructed for the Mathematical Quality of Instruction instrument, focusing in particular on the effects of varying the rater pool, subject matter content, observation procedure, and district context. Variation in the subject matter content of lessons did not affect rater agreement with master scores, but the evaluation of other portions of the validity argument varied according to the composition of the rater pool, observation procedure, and district context. These results demonstrate the need for conducting such analyses, especially for classroom observation instruments that are subject to multiple sources of variation.

Gauss–Markov model, Estimability of parametric functions, Unbiasedness of linear estimator, Natural restriction, Explicit restriction, Matrix rank method, OLSE, BLUE, 62J05, 62F30,

Although Imre Lakatos described the work published in his book Proofs and Refutations as a study of mathematical methodology, work which has been responded to and criticized by philosophers and historians of mathematics more on its own terms, a significant body of writing in the 30 years since its appearance has used it as a pertinent cognate text appropriable for school mathematics education. In this paper, we contrast the responses these two fields have generated, with an emphasis on that of mathematics education. Doing so offers a potentially salutary case study of how challenging and fraught it can be at times to undertake work at the nexus of history and philosophy on the one hand, while at the same time seeking to explore its possible relevance and significance for education. As our title suggests, we are concerned about the proliferating Lakatos personas that seem to exist, including a growing range of self-styled reform or progressive educational practices which get attributed to him.