Empirical arguments rely on examples without necessarily addressing all cases. Students should be skeptical of empirical evidence and should seek more secure arguments for generalizations, such as those that explain why a generalization is true for all cases. Generalizing on the basis of patterns in data is an important mathematical practice;…

When evaluators plan site-randomized experiments, they must conduct the appropriate statistical power analyses. These analyses are most likely to be valid when they are based on data from the jurisdictions in which the studies are to be conducted. In this method note, we provide software code, in the form of a SAS macro, for producing statistical…

Limited classroom time available in middle school mathematics classes forces teachers to choose between assisting students' development and assessing students' abilities. To help teachers make better use of their time, we are integrating assistance and assessment by utilizing a web-based system, ASSISTment, that will offer instruction to students…