School Science Review number 364
Number 364 - March 2017
|1||Contents and Editorial|
Newton’s Third Law
The truth, the half-truth or perhaps nothing like the truth – a tribute to John Warren (1923–2016)
|11|| Science Note: The famous 137-second plant hunt
Set the task for each pupil to collect a single specimen of as many different leaves as possible during 137 seconds.
|12|| Two simple methods to enrich the teaching of molecular genetics
A simple string model to demonstrate the importance of DNA gyrase in alleviating the strain due to supercoiling of DNA during replication in prokaryote chromosomes.
|16|| Science Note: Intermolecular forces
Many students are unclear about what van der Waals and London forces are if they consult several textbooks. To clarify, van der Waals forces represent the collective term for all types of intermolecular forces, which include London forces. In general, intermolecular forces are forces of attraction between neighbouring molecules. This article outlines the different types.
|18||Science Note: How much gas does a gasholder hold?
We are pretty good at giving ideas of scale when the objects are about human size: a finger is about 1 cm wide, an arm-stretch is about 1 m, a Smartie weighs about 1 g, a small apple weighs about 100 g and is attracted to the Earth with a force of about 1 N. It is a bit harder when talking about moles.
|19|| Science Note: Visualising energy transformations in electric circuits with infrared cameras
Increasingly affordable visualisation technology brings exciting opportunities for making the invisible appear visible. This can support the teaching and learning of many challenging physics concepts. Hand-held infrared (IR) cameras offer real-time instant visual feedback of temperature changes that correspond to energy transfer and transformations.
|22|| Science Note: Investigating the use of Electrolycra
The curriculum promotes health and well-being and this activity is an example of how technology is helping us monitor our fitness and therefore encourage a healthy lifestyle (National Curriculum in England KS3, age 11–14; Gas exchange systems and Scottish Curriculum for Excellence SCN 3-12b, age 10–13; the role of technology in monitoring health).
|25|| Science Note: The sky hook - a centre of mass illusion
In the UK, centre of mass experiments used to be plentiful and aimed at 12-13 year-old students. Currently, however, the topic of centre of mass and centre of weight seems to have shifted to an older age group (16-16 year-olds) to appear as a standard experiment on finding the centre of mass of an irregular-shaped card and a consideration of equilibrium, stability and toppling.
Promoted Feature - For the last two years, I have been visiting in schools across the UK and Ireland aiming to teach pupils and teachers about the marine environment. Under the banner of WhaleFest, the world’s largest marine festival, I visit schools and festivals with a life-size inflatable orca (aka a killer whale) aiming to enthuse people about the sea.
|31|| Using test data to find misconceptions in secondary science
Students, as well as teachers, often learn what makes sense to them, even when it is wrong. These misconceptions are a problem. The authors sought a quick, quantitative way of identifying student misconceptions in secondary science. Using the University of Toronto’s National Biology Competition test data, this article presents a method of quickly identifying misconceptions that agree with many facets of the extant misconception literature (ubiquity across subject areas, pervasiveness regardless of question difficulty, and distractive power). Seeking students’ most common wrong answer on a multiple-choice test is found to be a fast, reliable, and data-driven way to identify misconceptions.
|37|| What is a chemical element?
Contrary to current IUPAC recommendations, the chemical element X should be defined as the nucleus of the X atom. Consequently, different isotopes with their different nuclei belong to different elements, each one with its own physical and chemical properties. This view leads to the conclusion that we no longer have a periodic table of the elements, but a periodic table of isotopes instead.
|41|| Touch-initiated reaction of nitrogen triiodide as a template for activation energy classroom discussions
Activation energies form an energy barrier to a chemical reaction taking place. Simple collision theory, i.e. that particles need to collide to react, would suggest that activation energy is the energy needed to overcome a coulombic barrier provided by the negatively charged electrons contained within energy shells surrounding an atomic nucleus. Deriving activation energy from experiment is usually beyond the school curriculum. What can be demonstrated, however, is an almost barrierless reaction initiated by the slightest touch or vibration for the decomposition of nitrogen triiodide. This spectacular demonstration can be combined with calculations on bond enthalpies to help further understanding.
|47|| Using the REACT strategy to understand physical and chemical changes
Students often struggle to determine whether changes in matter are physical or chemical; for example, they may have difficulty labelling a candle melting as a physical change but a candle burning as chemical change. Here we describe a lesson that we used to integrate conceptual learning about physical and chemical changes using the ‘REACT’ strategy (relating, experiencing, applying, cooperating and transferring) using daily life examples. The activities cover one REACT cycle delivered over two lesson periods. In the activities, examples of physical and chemical change are taken from daily life. Students are actively involved in the activities and at the end of the experiencing stage, they should be able to distinguish physical and chemical changes and to define the changes occurring in the matter at the molecular level.
|53|| Heat transfer in a paper cup
The double-wall paper cup is an everyday object that can be used in the laboratory to study heat transfer. The experiment described here has been done by physics students aged 12–13 years; it can also be used in a different context to prompt debate about environmental issues.
|57|| The use of force notation to detect students’ misconceptions: mutual interactions case
Using a conventional notation for representing forces on diagrams, students were presented with questions on the interaction between two objects. The results show that complete understanding of Newton’s Third Law of Motion is quite rare, and that some problems relate to misunderstanding which force acts on each body. The use of the terms ‘action’ and ‘reaction’ in this specific context, compared with their general use, was also found to be misleading.
|65|| The ripple tank: management and observation
This overview is intended to help colleagues achieve successful and satisfying observations using a ripple tank. There are many observations to consider that can effectively illustrate reflection, refraction, interference and diffraction, but the most important consideration is to make every effort to enable students to see the effects we want them to see. Some of the content is based on articles written many years ago. This update is offered especially to help younger teachers develop confidence in the use of this equipment.
|77||Optimal learning in schools – theoretical evidence: Part 2 Updating Piaget
Part 1 in this four-part series of articles discussed Piaget’s theories of learning and development (Crossland, 2016). Part 2 explores how post-Piagetian researchers have addressed criticisms of Piaget’s theories by linking recent evidence including that from neuroscience. The outcomes show that good teachers make a difference by implementing classroom-based optimal learning strategies. This new evidence brings Piaget’s theories into the 21st century and leads to a clearer definition of optimal learning in the classroom.
|85|| Optimal learning in schools – theoretical evidence: Part 3 Individual differences
Parts 1 and 2 in this four-part series of articles (Crossland, 2016, 2017) discussed the recent research from neuroscience linked to concepts from cognitive development that brought Piaget’s theories into the 21st century and showed the most effective provision towards more optimal learning strategies. Then the discussion moved onto Demetriou’s latest thinking that explored the relationship between the developing mind and the developing brain. Part 3 outlines individual differences in learners with further implications for classroom practice leading to additional characteristics of optimal learning in the classroom.
|92|| Learning Landscapes: a form of formative assessment supporting assessment without levels
Learning Landscapes are assessment tools that can be used formatively to map progress in specific skills in the classroom and can contribute to learning without levels. Learning Landscapes can help both teachers and students recognise specific aspects of behaviour linked to a specific skill that provide evidence of their success in that skill. They can also be used to target next steps and therefore have a strong formative potential and can contribute to assessment without levels. Issues of gender and other diversity concerns can also be incorporated.
|101||Lab Equipment Special - During challenging times schools require trusted partners
Promoted Feature - These are challenging times for school budgets. We at the British Educational Suppliers Association (BESA) have been tracking school spend on education resources for over two decades, and haven’t seen a situation like this since the last recession.
• 117 This Book Thinks You’re a Scientist London Science Museum (llustrations by Harriet Russell)
|123|| App Reviews
• NAMOO Lite – Wonders of Plant Life
|125|| Science Websearch
|128||Special Issues and Index|