This article discusses the difficulties in conducting intervention research or evaluating intervention programs in a school setting. In particular, the problems associated with randomization and obtaining control groups are examined. The use of quasi-experimental designs, specifically a paired comparison design using the individual as his or her…

Discusses how clinicians and researchers can critically evaluate information from efficacy studies of language intervention programs. It argues for combining both experimental and nonexperimental approaches and suggests that the use of matching in nonrandomized studies allows for comparison of groups of children participating in an intervention…

Background: Multiplication and division by fractions are among the most troublesome concepts in the elementary mathematics curriculum. Recent studies have shown that preservice elementary teachers in the United States do not have deep understandings of these concepts. Effective ways to improve preservice teachers' conceptual understanding of these…