Lecture, two hours; discussion, two hours. Requisite: course 35. Introduction to four conceptual tools used to evaluate soundness of conclusions drawn from research evidence: notions of internal validity, statistical validity, construct validity, and external validity. Statistical validity requires basic fluency with quantitative data analysis, which students learn using statistical software R. Analysis of how values and beliefs shape quantitative education research and how research findings get translated when they are reported for popular media audiences. Quantitative background is not required. Letter grading.