Findings of a review of 64 meta-analytic articles show that experimental data and quasi-experimental or nonexperimental data are sometimes combined incorrectly. Discusses how guidance from proponents of meta-analysis fails to make clear the importance of not synthesizing different kinds of data. (SLD)

Discusses potential sources of self-selection bias in quasi-experimental evaluations of whole-school reform and considers how individual school-level data might be used to provide valid impact estimates. Develops an instrumental variable strategy that can be used to improve on common value-added estimators when only post-treatment measures are…

Presents a laboratory experiment demonstrating the binding of calcium/calmodulin to calmodulin kinase II, which is important in the metabolic and physiological activities of the cell. Uses SDS polyacrylamide gel electrophoresis (PAGE). (YDS)

Presents activities that involve the separation and identification of dyes from mouthwashes and the determination of their alcohol content. Provides a review of various analytical techniques and shows students that more than one instrument or technique may be required to analyze a product. (JRH)

Describes the design and construction of a safe student quantitative conductivity apparatus. Discusses experimental results. (JRH)

Describes an apparatus that is stable and accurate enough for quantitative conductivity experiments but maintains the simplicity of construction and use as well as low cost. Discusses principles and implementation and the performance of the assembled apparatus. (JRH)

Presents an experiment that challenges the claim that sprouting radish seedlings release chemicals into the environment that inhibit germination of lettuce seeds. Reports that although no simple allelopathic demonstration was observed, the experiment provides fertile ground for further experimentation in inquiry-based laboratory experiences. (JRH)

Examines Rousseau's life as continuous experimentation in learning, systematic study, and mechanical arts. Stresses that Rousseau saw that education's wider purpose is to prepare individuals to construct a better society. (SK)

Published studies of hypermedia as an educational technology that have emphasized quantitative and empirical assessment of outcomes were reviewed. The evidence to date suggests that hypermedia benefits in education are limited to learning tasks depending on repeated manipulation and searching of information. Implications for instruction and…

Describes a chemistry outreach program where graduate student volunteers perform shows to excite high school students about science. Lists the experiments and demonstrations performed in the shows, and concludes that this outreach benefits both the high school student audience and the graduate student volunteers. Contains 21 references. (JRH)

Describes an experiment to measure the acceleration of a bungee jumper. Uses energy considerations to explain this anomalous acceleration and presents experimental results using several different types of ropes and a chain. (JRH)

Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

Presents investigations of leaf surface wetness that provide ideal opportunities for students to explore the relationships between leaf form and function, to study surface conditions of leaves and plant physiology, and to make predictions about plant adaptation in different environments. Describes simple procedures for exploring questions related…

Presents 6 short experiments with liquid nitrogen that 12- and 13-year-old students can safely perform under close supervision. Helps the students in learning a number of basic chemical principles while spurring their curiosity and showing them how much fun chemistry can be. (JRH)

Introduces a follow-up laboratory experiment demonstrating the formation change when calcium binds to calmodulin. This conformation change allows this complex to bind to a target protein. Presents the necessary information to conduct the experiment and discusses the results. (YDS)