Search results for "Science instruction"

The exclusive language of science? Comparing knowledge gains and motivation in English-bilingual biology lessons between non-selected and preselected…

2018

ABSTRACTThe dominant role of English as the global language of science entails a requirement for science teachers to equip their non-native English-speaking students with receptive and productive l...

K-means Clustering to Study How Student Reasoning Lines Can Be Modified by a Learning Activity Based on Feynman’s Unifying Approach

2017

Background:Research in Science Education has shown that often students need to learn how to identify differences and similarities between descriptive and explicative models. The development and use of explicative skills in the field of thermal science has always been a difficult objective to reach. A way to develop analogical reasoning is to use in Science Education unifying conceptual frameworks.Material and methods:A questionnaire containing six open-ended questions on thermally activated phenomena was administered to the students before instruction. A second one, similar but focused on different physical content was administered after instruction. Responses were analysed using k-means Cl…

Systematic Approach for Calculating the Concentrations of Chemical Species in Multiequilibrium Problems: Inclusion of the Ionic Strength Effects

2012

A general systematic approach including ionic strength effects is proposed for the numerical calculation of concentrations of chemical species in multiequilibrium problems. This approach extends the versatility of the approach presented in a previous article and is applied using the Solver option of the Excel spreadsheet to solve real problems such as the calculation of the pH of buffer solutions at any ionic strength. It is useful for undergraduate programs, in post-graduate programs, and in professional laboratories to predict experimental conditions.

Warming of water in a glass

2016

The article focuses on the process of water warming from 0 °C in a glass. An experiment is performed that analyses the temperature in the top and bottom layers of water during warming. The experimental equipment is very simple and can be easily set up using devices available in schools. The temperature curves obtained from the experiment help us to understand the process of convection in the glass and to determine the temperature at which the density of water is maximum. In addition, computational fluid dynamics—CFD modeling is carried out to facilitate better comprehension of the phenomenon observed in the experiment.

Disassembling the classroom – an ethnographic approach to the materiality of education

2012

The ethnography of education is challenged by the materiality of the classroom. Ethnographic accounts of school lessons mostly highlight language and interaction and offer no suitable methodology for researching objects and their role in the classroom. Moreover, objects are part of complex and interwoven assemblages involving human actors, practices and things. As such, their contribution to human practices often remains unnoticed in the background of routine activities. In order to make the materiality of practice available to ethnographic observation, we thus have to analytically disassemble these assemblages. An ethnographic approach that draws on practice theory and concepts developed i…

Teacher orchestration of classroom interaction in science: exploring dialogic and authoritative passages in whole-class discussions

2019

Whereas science is fundamentally a result of a dialogic debate, the authoritative approach has been conceived of as a fundamental part of school science. Dialogic interactions encompass the mutual appreciation of different ideas manifested in teacher supportiveness toward students and, in authoritative interactions, the focus is more on the science’s or teacher’s point of view. Whereas dialogic and authoritative interactions have been viewed as oppositional in recent educational research, authoritative interactions could well be the seed for and give strength and meaning to dialogic interactions, and thus, to the overall dialogue. The focus in this study is on the interplay between authorit…

Undergraduate experiment with fractal diffraction gratings

2011

We present a simple diffraction experiment with fractal gratings based on the triadic Cantor set. Diffraction by fractals is proposed as a motivating strategy for students of optics in the potential applications of optical processing. Fraunhofer diffraction patterns are obtained using standard equipment present in most undergraduate physics laboratories and compared with those obtained with conventional periodic gratings. It is shown that fractal gratings produce self-similar diffraction patterns which can be evaluated analytically. Good agreement is obtained between experimental and numerical results. © 2011 IOP Publishing Ltd.

Oxidation of secondary alcohols by duckweed: A biotransformation experiment for undergraduate students

1988

An approach to the Venturi effect by historical instruments

2021

Student understanding of the laws that describe the flow of a fluid is often hampered by a defective knowledge of basic classical mechanics (kinematics, statics, dynamics, and conservation laws) and by wrong common-sense ideas about quantities related to fluids, such as velocity and pressure. A pedagogical discussion about the Venturi effect, based on experiments inspired by historical instruments, may be an effective way to introduce students to these laws. In this paper, we discuss an approach to the understanding of the Venturi effect based on the study of historical instruments and on simple experiments. In particular, after a presentation of the Venturi effect, also from a historical p…

Teaching Inorganic Photophysics and Photochemistry with Three Ruthenium(II) Polypyridyl Complexes: A Computer-Based Exercise

2015

Among computational methods, DFT (density functional theory) and TD-DFT (time-dependent DFT) are widely used in research to describe, inter alia, the optical properties of transition metal complexes. Inorganic/physical chemistry courses for undergraduate students treat such methods, but quite often only from the theoretical point of view. In the calculation exercise herein described, students are guided step by step through the computational study of the photophysics and photochemistry of polypyridyl Ru(II) d6-metal complexes. In particular, by means of DFT and TD-DFT calculations, they are asked to examine and interpret a set of experimental data describing the absorption, emission, and ph…