Nitrate assimilation by plants provides an excellent system for demonstrating control of gene expression in a eukaryotic organism. Describes an assay method that allows students to complete experiments designed around the measurement of nitrate reductase within a three-hour laboratory experiment. (PR)

Explains how sweet potato roots can be used for plant tissue culture for biology laboratory instruction. (PR)

Explains that discussions should be used to help students think about their experiences with hands-on science learning. Making hands-on science "brains-on" will help challenge student's misconceptions. (PR)

Addresses some basic aspects of Archimedes' law. Focus is on potential energy relationships so as to elucidate some common misunderstandings and to facilitate making bridges with other physical topics. A spreadsheet model is used as a simulation tool. (Author/NB)

Describes a project undertaken to increase the pedagogical content knowledge of Pakistani science and math teachers (n=31). Presents specific features of the Subject Specialist Teacher Programme in relationship to both the contextual quality and relevance of the initiative. Addresses challenges and possibilities associated with the model as a…

Discusses students' perceptions of using writing as a component of their science learning. Results, collected over four years, are organized to include students' perceptions of writing in science, learning, ownership, purpose, and science. These results are then discussed in terms of students' developing metacognition and epistemologies of…

This study evaluated an experimental science program which altered both content and instructional methods in teaching science to at-risk and learning-disabled middle school students. Content was framed with concepts and principles, and instruction was explicit, using rules to guide classroom activities for six students in a pull-away setting.…

Discussion of how the nature and use of visual and verbal meaning-making systems vary across formats. Focuses on a comparative study of CD-ROMs and printed books dealing with scientific concepts in upper primary grades. Topics include linguistic and visual semiosis; the use of images; and meanings in images. (Author/LRW)

Describes the measurement of blood speed in blood vessels by using the Doppler effect. (WRM)

Finds that interpretation of Galileo's only known experimental manuscript produces some interesting questions that offer pedagogical applications. Promotes classroom "research games" consisting of reconstructed experiments with Galileo's inclined plane and with other instruments to allow further speculation. (Author/WRM)

Presents a hands-on activity designed to be a simulation of meiosis. (WRM)

Describes 10 experiments designed to serve as a qualitative introduction to Rayleigh-Taylor Instability. (WRM)

Describes a safe but qualitative alternative to an experiment in which bullets are shot into wooden blocks from below, with some bullets hitting the blocks in the center and others off-center. Explains why the off-center blocks reach greater heights in spite of the fact that the bullet's energy is divided between translational and rotational…

Explains the strange effect a crosswind has on motion. (WRM)

Presents results of an exam designed to uncover misconceptions about molecular shape and bonding based on the VSEPR model. Results are reported for high school students, beginning and advanced undergraduate students, beginning and advanced graduate students, and college-chemistry faculty. Finds that students seem to acquire both recall and…