Explores the reactions of third-year pupils to their science lessons. Discusses the extent to which these boys' and girls' reactions can be used to predict enrollment in the different branches of science in their fourth year. Describes ways to encourage students to continue in science. (CW)

Describes a study of students' ability to balance equations. Answers to a test on this topic were analyzed to determine the level of understanding and processes used by the students. Presented is a method to teach this skill to high school chemistry students. (CW)

Describes the characteristics of task-centered explorations. Provides definitions and examples of types of task-centered activities. Analyzes factors which produce an uneven distribution pattern in the type of explorations that pupils experience. Discusses the implication of these analyses for classroom teachers. (CW)

This article presents the teaching materials developed by the Science and Technology in Society Project (SATIS). Discusses how to demonstrate and assess the relevance of science. (CW)

Describes a basic biotechnology investigation that includes restriction and ligation of plasmid DNA, transformation of bacteria and cloning of these bacterial cells. Discusses laboratory procedures and another activity in the identification of unknown plasmids by studying agarose gel electrophoresis photographs. (CW)

Introduces an experiment exhibiting blue and yellow-orange coloration in the plane of vibration of a vibrating string. Provides pictures and the experimental set-up. (YP)

Describes a student learning activity used to teach the meaning of percentage composition, mole concept, selective precipitation, and limiting factors. Presents two word problems and their solutions. (CW)

Describes an extended summer field trip through nine states and Canada on geology, biology, and ecology. Discusses how this trip helps students learn about the world they live in by first-hand experience and by learning to take responsibility for their own education. Highlights the history, organization, and value of this trip. (CW)

Describes a technique of impregnating small amounts of sandy sediment in a quick curing resin for microscopic examination. Details the preparation of materials. Suggests laboratory exercises based on this preparation. (CW)

Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

Introduces a demonstration kit for understanding conductivity by using several fruits and vegetables. Provides a parts list and assembly instructions for the "lemon screamer." (YP)

Introduces a construction method for a bubble made of polyurethane plastic and its applications in an ecology classroom. Provides the materials list, directions for bubble construction, and classroom activities. (YP)

Introduced is an inexpensive laboratory apparatus for first-year high school chemistry students. Presents information on materials, construction procedures, and activities for students. (YP)

Presents a method for representing students' knowledge about basic scientific concepts by classifying ideas produced in a free-writing task. Implies that those differences which exist can best be attributed to general fluency in the language of instruction rather than factors that are specific to the learning of science. (Author/CW)

Reports on a process which allows active study of mutating the characteristics of a population of organisms. States that the program, written in C, should run on a MS/DOS system with 640K; CGA is required for graphics output. Describes implementation procedures and two examples using the program. (RT)