The surface-to-volume ratio is an important quantity in thermal physics. For example it governs the behaviour of heating or cooling of physical objects as a function of size like, e.g. cubes or spheres made of different material. The starting point in our paper is the simple physics problem of how cheese cubes of different sizes behave if heated…

An evaluation of a course aimed at developing university students' understanding of the nature of scientific measurement and uncertainty is described. The course materials follow the framework for metrology as recommended in the "Guide to the Expression of Uncertainty in Measurement" (GUM). The evaluation of the course is based on…

In this paper, we show the potential of webcams as precision measuring instruments in a physics laboratory. Various sources of error appearing in 2D coordinate measurements using low-cost commercial webcams are discussed, quantifying their impact on accuracy and precision, and simple procedures to control these sources of error are presented.…

Since 1999, Slovenia has been in the process of introducing nine years of compulsory education to replace the previous eight-year system of compulsory education. Under the new system, the school entry age is six years rather than the former seven years. This reform of the system necessitated a number of other changes, such as those relating to the…

Biobottles are miniature ecosystems made from 2-liter plastic soda bottles. They allow students to explore how organisms in an ecosystem are connected to each other, examine how biotic and abiotic factors influence plant and animal growth and development, and discover how important biodiversity is to an ecosystem. This activity was inspired by an…

Contends that demonstration lecturing is a valuable science teaching approach. Highlights the benefits of this technique and identifies sources of information for teachers. Provides a listing of popular science lectures suitable for chemistry classes. Describes in detail the "Major of Chemistry" demonstration. (ML)

Describes a chemistry experiment appropriate for the day before Christmas vacation. Students prepare candy canes by following a recipe written in chemical terms. This illustrates that food is composed of chemicals and that the processes involved in cooking are chemical and physical changes. (JR)

Describes experiences, or "lab puzzles," which will help students develop problem-solving skills in a laboratory setting. Outlines procedures for developing techniques, setting boundaries, and finding the number of molecules of water in Lake Erie. (RT)

The purpose of this study was to determine the concerns of Texas science teachers about the 40 percent laboratory time rule just prior to enforcement and at the end of its first year of implementation. The methodology, results of the first and second years, conclusions, and implications for teaching science are discussed. (KR)

In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

Stomata are the pores on leaves through which carbon dioxide, oxygen, and water vapor are exchanged with the atmosphere. Researchers have found that leaf stomatal densities change in response to several environmental variables, including humidity, light intensity, and atmospheric levels of carbon dioxide, a greenhouse gas (Van Der Burgh, Dilcher,…

Plant tropisms--their directional movement in response to stimuli--are a fundamental concept in plant science and excite students because they are the observable signs of life in plants. Unfortunately, the precollege teaching literature is full of tropism misconceptions. An inexpensive clock clinostat is invaluable for student gravitropism and…

This book presents essential learning approaches. It introduces educational and training activities, as well as various innovative methods aiming at the development of practical skills, in order to strengthen the continuous process of environmental education, and in particular the education for sustainable development (ESD). In doing so, it…

Advances in biology are prompting new discoveries in the biotechnology, pharmaceutical, medical technology, and chemical industries. This paper presents a detailed description of an anion exchange chromatography experiment using a pair of colorful proteins and summarizes the effect of operating parameters on protein separation. This experiment…

An ozonolysis experiment, suitable for undergraduate organic chemistry lab, is presented. Ozonolysis of eugenol (clove oil), followed by reductive workup furnishes an aldehyde that is easily identified by its NMR and IR spectra. Ozone (3-5% in oxygen) is produced using an easily built generator. (Contains 2 figures and 1 scheme.)