Reported are observational limits of detectability for several single stimulus and multi-stimuli observation tasks in secondary level chemistry. Provided are tables of actual results obtained including type of observation, chemical system used, method of determining stimulus magnitude, and observational thresholds. (Author/YP)

Provides a description of a computer program developed to supplement instruction in testing of antibiotics on clinical isolates of microorganisms. The program is a simulation and database for interpretation of experimental data designed to enhance laboratory learning and prepare future physicians to use computerized diagnostic instrumentation and…

Presents a learning cycle lesson plan in which students investigate the question of how cells divide. Students use microscopes to explore actual plant root and stem tissues to generate and test hypotheses to answer the question. Includes teacher material, student material, and teaching tips. (MDH)

Differences in science achievement between males and females have been examined either directly or indirectly in a variety of studies. This investigation reviewed a quantitative synthesis of correlational research on science affect, ability, and achievement conducted by Steinkamp and Maehr. Their findings were reassessed by employing a…

Describes an exercise which provides a small data set consisting of the localities where various genera of a fictitious group of fossil "Archaeomorphs" have been found on various continental blocks. The activity can be used to develop hypotheses regarding plate tectonic processes and the present arrangement of fossil localities. (TW)

Presents an activity that allows students to experience the type of discovery process that paleontologists necessarily followed during the early dinosaur explorations. Students are read parts of a story taken from the "American Journal of Science" and interpret the evidence leading to the discovery of Triceratops and Stegosaurus. (PR)

Provides methods for cooperative, student investigation of weather data similar to methods currently used by atmospheric scientists. Utilizes spreadsheets to focus on the analysis and interpretation of wind frequency data for a small town in Oregon. (JJK)

Describes an extended problem-solving activity utilizing drift-bottles that encourages students to deduce probable and great-circle drift-bottle routes, to use logic based on unit calculations, and to estimate the distance traveled and the minimum velocity of these drift-bottles. Includes materials needed, learning objectives, procedures,…

Describes the construction of durable, inexpensive and large sand-hourglasses for use in controlled experiments that allow students to observe, infer, measure, record data, and predict. This hands-on activity is designed to take place over a three-day interval. Includes materials needed, techniques, procedures, follow-up activities, and resource…

Described is a membrane experiment that provides students with experience in fundamental engineering skills such as mass balances, modeling, and using the computer as a research tool. Included are the experimental design, theory, method of solution, sample calculations, and conclusions. (KR)

Describes an activity for determining how long and when a tree lived by comparing its ring sizes with local precipitation records. Suggests benefits for this type of dendrochronology activity. (TW)

A study was conducted on the enrollments of students (N=13,856) in first and second year science courses at Pima Community College, Arizona, over a 5-year preiod. Of those students who passed these courses with a C grade or better (N=5,974), frequency distributions by sex were made. It was found that the distribution of male/female registered as…