Scientists use models to describe and explain observed physical phenomena and to predict the outcomes of new phenomena. Choosing a productive model for describing or explaining a phenomenon is a routine part of the work of scientists but a rare exercise for our students. Students have difficulties understanding the meaning of the word "model" and…

Used since the time of the ancient Egyptians as a method for transferring liquids from one vessel to another, the siphon is a dependable tool. Although, the act of siphoning beer from a fermentation barrel or wine from a demijohn is a skill that has been passed down from generation to generation, do we really know how the siphon works? It is…

A solid foundation of chemistry principles is only gained through a true comprehension of the material as opposed to pure memorization. One of the most fundamental concepts in chemistry is that of determining the amount of product formed in a chemical reaction when one of the reactants is limiting. To increase students' comprehension of this…

The notion that acid salts exist only for diprotic and polyprotic acids is found in many high school and university textbooks, although the "only" condition is not always stated explicitly. A fairly simple experiment shows that there is a pronounced exothermic effect when pure acetic acid is added to potassium acetate. Experiments with similar…

Demonstrating how surface chemistry and self-assembled monolayers (SAMs) control the macroscopic properties of materials is challenging as it often necessitates the use of specialized instrumentation. In this hands-on experiment, students directly measure a macroscopic property, the floatation of glass coverslips on water as a function of…

The recommendations of the United States President's Council of Advisors on Science and Technology and the multi-agency National Nanotechnology Initiative (NNI) identified the need to prepare the workforce and specialists in the field of nanotechnology in order for the United States to continue to compete in the global marketplace. There is a…

Science is always changing. Its very nature requires that scientists constantly revise theories to make sense of new observations. As they learn science, students are also constantly revising how they make sense of their observations, which requires comparisons with what they already know to process new information. A teacher can take advantage of…

"I Wonder" boards are a teaching strategy that can be used in the classroom, as well as during science learning opportunities in nonformal settings, such as after-school science programs or summer camps.This simple strategy has led to deeper science exploration in 4-H, as young people learn alongside program staff, teachers, or…

Cell-free protein synthesis (CFPS) has emerged as a practical method for producing a broad variety of proteins. In addition, the direct accessibility to the reaction environment makes CFPS particularly suitable as a learning vehicle for fundamental biological concepts. Here, we describe its implementation as a teaching tool for a high school…

Previously, we found that: (i) many students were unable to construct representations of simple molecular structures; (ii) a majority of students fail to make the important connection between these representations and macroscopic properties of the material; and (iii) they were unable to decode the information contained in such representations.…

This study explores middle and high school students' understanding of the particulate nature of matter after they were taught the concept. A total of 87 students (41 high school and 46 middle school) participated in the study. Findings suggest that students held misconceptions about the law of conservation of matter, chemical composition of matter…

An educational demonstration shows the combustion of carbon to carbon dioxide and then the reduction of carbon dioxide to carbon. A melee diamond is the source of the carbon and the reaction is carried out in a closed flask. The demonstration helps students to realize that diamonds are made of carbon and that atoms do not change or vanish in…

The electrochemical hydrogen evolution reaction (HER) is growing in significance as society begins to rely more on renewable energy sources such as wind and solar power. Thus, research on designing new, inexpensive, and abundant HER catalysts is important. Here, we describe how a simple experiment combined with results from density functional…

This study investigates ways to enhance secondary school students' knowledge transfer in complex science domains by implementing question prompts. Two samples of students applied two web-based models to study molecular genetics--the model of genetic code (n = 258) and translation (n = 245). For each model, the samples were randomly divided into…

A compass is an excellent classroom tool for the exploration of magnetic fields. Any student can tell you that a compass is used to determine which direction is north, but when paired with some basic trigonometry, the compass can be used to actually measure the strength of the magnetic field due to a nearby magnet or current-carrying wire. In this…