Red onion, "Allium cepa," juice can dye a cloth sample green upon the addition of alum, aluminum potassium sulfate, and this sample can turn red when subjected to an acidic solution. When the red-colored sample is washed with a neutral or alkaline aqueous solution, its color turns green again. These experiments illustrate color changes…

The digestive system is a fundamental topic in biological science teaching. Despite its importance, the level of students' knowledge on the topic appears to differ from recommended levels at several educational grades. Their knowledge also seems to be resistant to change; therefore, this discrepancy may be viewed as an epistemological obstacle to…

Science is the study of the world around us, and a scientist's job is to ask questions about the world and then experiment to find the answers. There is not a more natural scientist than the Elementary child, whose reasoning mind is eager to ask questions, investigate, and discuss and compare findings with their peers. In this article, the authors…

There is an increasing focus across all educational sectors to ensure that learning objectives are aligned with learning activities and assessments. An attractive approach previously published is that of curriculum alignment projects. This paper discusses the use of the fun and famous "Elephant's Toothpaste" experiment as a customizable…

Details a laboratory experiment designed to extend the calcium PVC matrix membrane ion-selective electrode studies to complex formation equilibria. (Author/MA)

Presented is a laboratory exercise that utilizes the natural yeast carbonation method of making homemade root beer to study fermentation and the effect of variables upon the fermentation process. There are photographs, a sample data sheet, and procedural hints included. (Author/MA)

The use of the earthworm as a laboratory animal for studying the effect of starvation on nitrogen metabolism is discussed. Simple techniques and methods are presented allowing in vivo physiological responses to be compared with changes in the enzyme potential of gut tissue. (Author/MA)

Describes a laboratory experiment demonstrating the aldehyde oxidase activity in wild type and mutant fruit flies using a quantitative assay. The experiment can be performed in one hour. (MA)

This experiment is designed specifically for students with little knowledge of radical reactions and provides an introduction to the gas-phase chemistry of radicals. Experimental planning based on the student's own observation is an important component of the experiment. (Author/MA)

Describes two demonstration experiments for the chemistry laboratory: (1) Thermodynamic vs kinetic control and (2) Acid-Catalyzed Hydrolysis of Starch. (MA)

Methods are described for the induction and identification of respiratory deficient mutants in yeast. Practical schemes are given to enable students to obtain dose-response information for physical and chemical mutagens such as heat, ultraviolet light, or acriflavine. A simple test for environmental mutagens is described. (Author/MA)

The rhizosphere is the area directly surrounding the roots of a plant and an area of tremendous microbial growth. This article described techniques for studying this soil biome. Illustrations are included. (MA)

Describes an experiment used to demonstrate the relationship among hypertonic, hypotonic, and isotonic solutions and provides and open-ended research opportunity for additional individual investigation by students. (Author/MA)

Describes a blood coagulation test developed by two high school biology students. Although the test lacks some precision, results indicate that the technique is comparable to standard methods used in laboratories. (MA)

This collection of lesson plans designed for teachers of 4th- through 12th-grade students utilizes an assortment of teaching strategies for topics related to coal and the coal industry. Activities cover the following topics: coal formation; coal identification; "the geologist's dilemma" (a supply and demand activity); geologic time and…