As part of an interview protocol investigating teachers' pedagogical content knowledge (PCK) in statistics, 40 teachers were presented with a newspaper article reporting a phone-in survey about the legalisation of marijuana. The article and a question about the reliability of the sample had earlier been used in student surveys, and three student…

This paper provides practical guidance for researchers who are designing and analyzing studies that randomize schools--which comprise three levels of clustering (students in classrooms in schools)--to measure intervention effects on student academic outcomes when information on the middle level (classrooms) is missing. This situation arises…

When attempting to determine if an intervention has a causal impact, the "gold standard" of program evaluation is the randomized controlled trial (RCT). In education studies random assignment is rarely feasible at the student level, making RCTs harder to conduct. School-level assignment is more common but this often requires considerable resources…

Virtual Comparison Groups (VCG) were developed by the Northwest Evaluation Association as an alternative to conventional controlled experiments for social science researchers working in the field of education. The VCG is generally a group of up to 51 students who are matched, based on key characteristics of the student and school, to a single…