The precise measurement of conductivity of a semiconductor film such as polypyrrole (Ppy) should be carried out by the four-point probe method; however, this is difficult for classroom application. This article describes the development of a new, convenient, handmade conductivity device from inexpensive materials that can measure the conductivity…

A modified technique for demonstrating the magnitude of Avogadro's number using a new Raspberry Pi computer and the Python language is described. The technique also provides students the opportunity to review dimensional analysis.

"Floating" teachers, or teachers without their own classroom, experience unique affordances and constraints as they develop professionally. To increase the knowledge in this area, this study looks at how traveling to different classrooms affects beginning secondary science teachers' development and instruction. The participants in…

The South African science curriculum advocates an inquiry-based approach to practical work. Inquiry is a complex and multifaceted activity involving both cognitive and physical activity; thus, paper-and-pencil items do not provide the authentic context for this assessment. This study investigates the construct validity of inquiry-related questions…

We compare the period of oscillation of an ideal simple pendulum with the period of a more "real" pendulum constituted of a rigid sphere and a rigid slender rod. We determine the relative error in the calculation of the local acceleration of gravity if the period of the ideal pendulum is used instead of the period of this real pendulum.

Constructing explanations and participating in argumentative discourse are seen as essential practices of scientific inquiry. The objective of this study was to explore the elements and origins of pre-service secondary science teachers' alternative conceptions of tidal phenomena based on the elements used in Toulmin's Argument Model through…

A challenge: Can you create a stable top from a single paper clip? Several interesting solutions to this problem were provided by Takao Sakai from Japan, the requirement of each being that the center of gravity be located on the vertical y-axis at the center of the top. In the simplest configuration, we see that there exists a single angle ?…

We present the development of a construct map addressing the reason for the seasons, as a subset of a larger learning progression on celestial motion. Five classes of 8th grade students (N?=?38) participated in a 10-day curriculum on the seasons. We revised a hypothetical seasons construct map using a Rasch model analysis of students'…

This paper selects six key alternative conceptions identified in the literature on student understandings of chemical bonding and illustrates how a historical analysis and a textbook analysis can inform these conceptions and lead to recommendations for improving the teaching and learning of chemical bonding at the secondary school level. The…

This article presents a problem-based learning (PBL) approach to teaching elementary biochemistry to undergraduate students. The activity was based on "the foods we eat." It was used to engage students' curiosity and to initiate learning about a subject that could be used by the future teachers in the high school. The experimental…

Background: Asking questions is an important scientific practice, and students around the world are expected to learn how to ask their own research questions while performing inquiry. In contrast to authentic scientific inquiry, in most simple inquiry tasks that are carried out in schools, the research questions are given to the students. Here, we…

The literature on science education reveals a worldwide decline in young people's interest in the study of sciences. This lack of interest has resulted in low enrolment rates in science-related courses at tertiary level. Researchers have suggested, among other innovations, the use of context-based teaching approaches as a way of motivating…

This study reports the use of data mining tools in order to examine the influence of the methodology used in chemistry lab classes, on the weight attributed by the students to the lab work on learning and own motivation. The answer frequency analysis was unable to discriminate the opinions expressed by the respondents according to the type of the…

Research has shown that students have tremendous difficulties developing a qualitative understanding of wave optics, at all educational levels. In this study, we investigate how three different approaches to visualizing light waves affect students' understanding of wave optics. In the first, the conventional, approach light waves are represented…

Currently, in science teaching and in particular, natural science teaching there are concepts in the school that have a high level of abstraction. Concepts, such as atom, gene, mole and energy, among others are difficult to explain in an understanding manner to students. This situation requires the teacher to design alternative strategies to…