Table of Contents
PRIMARY CORRECTIONS - LIGHT SHOWS:
Light Shows resources:
- Light Shows - Year 5 Physical Sciences. Source: Primary Connections - Light Shows
- ATSI Astronomy: http://www.assa.org.au/media/2912/aaaip.pdf
And for anyone bored already:
Stated Outcomes:
Alignment with the Australian Curriculum: English and Mathematics:
PAGE 7: Language for interaction ACELA1502: Understand how to move beyond making bare assertions and take account of differing perspectives and points of view (Lessons: 1, 4, 5, 7)
A CRITICAL EVALUATION - PRIMARY CONNECTIONS 'LIGHT SHOWS'
EXPLANATION:
This section includes unedited example content from the PrimaryConnections 'Light Shows' resource.
It includes a number of comments, inserted in context, to highlight issues that will help teachers better understand the science of 'light'.
A number of sample Primary Connections 'Light Shows' lessons are analysed, high-lighted and annotated using the 
flag.
SUMMARY:
Primary Connections: A place where a professor’s lecture notes are transferred to the students' note book, without passing through the brains of either. 1)
FOREWORD: 'Am I just a pedantic science nitpik'? 2)
In 1964 the eminent, Nobel prize winning mathematician and physicist Richard Feynman served on the State of California's Curriculum Commission and saw how the Commission chose math textbooks for use in California's public schools. In his acerbic memoir of that experience, titled “Judging Books by Their Covers,” he said:
“all the books … said things that were useless, mixed-up, ambiguous, confusing, and partially incorrect. How anybody can learn science from these books, I don't know, because it's not science.”
“The reason was that the books were so lousy. They were false. They were hurried. They would try to be rigorous, but they would use examples (like automobiles in the street for “sets”) which were almost OK, but in which there were always some subtleties.
The definitions weren't accurate.
Everything was a little bit ambiguous – they weren't smart enough to understand what was meant by “rigor.” They were faking it. They were teaching something they didn't understand, and which was, in fact, useless, at that time, for the child.” - Source: 3)
The above is a very nice summary of Primary Corrections content and the stuff below only provides some quick and superficial supporting evidence (due to time restrictions). A detailed analysis would be far more scathing.
A 'Light Shows' Review Starts Here:
The Primary Corrections Teacher background information (the professors lecture notes) does accurately describe current scientific understanding.
Unfortunately the same cannot be said for the process designed to transfer the 'information about science' into 'teaching kids how to better understand science and light'.
There is minimal explicit focus on the use of 'scientific method' and/or 'scientific language' either in the classroom activities or in their analysis. Where data is collected, there no mention of the benefits of technology (say use of a spreadsheet) compared with data collection and analysis based on open discussion and individual bits of paper.
Many of the classroom exercises and activities do not link well to, and in some instances contradict the Teacher background information
For example:
Lesson 3 Teacher background information says: “Light radiates from its source in straight lines. If it encounters matter, it is reflected, transmitted (let through) or absorbed (transformed into heat energy).” 4) And Later, 'Light will not travel through a bent tube as light travels in straight lines through the air' 5).
And later…
“When light is transmitted through two transparent materials, such as air and water, it can be bent where the two surfaces meet in a process called refraction.”
If we state that light radiates in a straight line… students may find it confusing and/or contradictory (if left unexplained), to say elsewhere in the same document that light is bent 'in a process called refraction'? - See this simple experiment: http://www.arvindguptatoys.com/toys/Addsugarbendlight.html
Some students/teachers may be aware that light also 'bends' around objects and bends under the influence of gravity. There is no explanation offered by Primary Corrections to resolve this apparent contradiction. Teachers may not have sufficient understanding to identify or resolve this or similar apparent contradictions. This may be acceptable for kindy, but surely not years 5, 6 or beyond.
As presented, the investigative tools are boring and 'unscientific' and largely mediated more by open discussion than evidence.
For example:
Is a 'Peek Box' a well recognised scientific, educational or fun device? What evidence exists that the device provides any valid/persuasive data in support of a scientific understanding about the nature of light? There are better devices/methods to engage students and help them obtain the stated science and literacy outcomes for this unit.
The investigative activities are not only boring, but largely ignore 'scientific method':
Data analysis is mostly consensus/discussion based, with no guarantee that the explainer (the teacher) has any better understanding of the science than the designer of the activity or those discussing it (the students).
The stated intention of this unit is to investigate light using evidence based, scientific method to help students 'understand how to move beyond making bare assertions' 6)
It is difficult to see how this unit achieves the stated outcome:
End of review summary
A MORE DETAILED OVERVIEW
About The 'Teacher background' information:
NOTE: All page numbers are those displayed in the footer of the source document: These may not be the same page numbers assigned by the end-user's pdf reader.
Introduction to light
- What we call light is a specific type of energy called ‘visible light’ — the light that humans can see.7)
- Electromagnetic radiation can travel through a vacuum and through transparent liquids or solids.
: WRONG: When using scientific language, what we call 'light' includes electromagnetic energy that humans cannot see, such as infrared and ultra-violet light
: WRONG: Most liquids and solids are transparent. Many liquids or solids that appear to be opaque when viewed by humans are in fact transparent to infrared light and xrays. 8)
Student Conceptions
- Light is not considered to ‘travel’; rather it is thought to just exist
- They also might think that light from weak sources doesn’t travel as far as light from
strong sources. In fact, all light travels from its source in all directions, regardless of its intensity, unless interrupted by matter, such as air, water or an object, where it is reflected, transmitted or absorbed.
There are numerous non-scientific conceptions around the reasons we can see objects. Some students might think that sight or light travels from our eye to the objects we look at or that light remains on the objects so that we can see them.
They might have no conception that light from a source such as the Sun is reflected from the object into our eyes so that we can see it.
Students might also think that owls, bats and cats can see in complete darkness and that humans also can see (not well) in complete darkness if we wait a while for our eyes to adjust. When there is minimal light our pupils widen to make better use of the available light. No animal can see in the complete absence of light. Nocturnal animals, for example, owls, have very light-sensitive eyes which allow them to see when there is very little light. However, because they are so sensitive to light they cannot stand the brightness of daylight.
Non-scientific conceptions about the behaviour of light are common. Students might think that light only bounces off luminous objects or very shiny ones, for example, mirrors. Light reflects off shiny surfaces in an ordered way. Light also reflects from dull surfaces but in a more scattered way 9)
Research overwhelmingly shows that most primary school teachers hold the same misconceptions and thus tend to reinforce student misconceptions rather than correct them. Primary Connections does nothing to address that.
Key lesson outcomes
Science:
Students will be able to represent their current understanding as they:
- describe how light travels
- discuss how light enables our eyes to see
- describe and visually represent their understanding of reflection, absorption and refraction of light.
Literacy:
Students will be able to:
- contribute to discussions about dark and light
- record ideas using a think-box strategy
- contribute to a science chat-board and word wall.
Is it appropriate to use technology tools for any of the above?
SESSION 1 & 2 - Pages 12 -
WillAre the same diagnostics/questions also relevant for teachers? How do we know that teachers have sufficient understanding to avoid re-enforcement of student misconceptions?
For example, how many teachers could correctly answer and explain these questions copied (unedited) from Page 13 10)?
- How does light help us to see?
- How does light travel and how far does it travel?
- What is a shadow?
- What happens when light from a torch hits:
- black card?
- a mirror?
- Draw what you see when a glass of water has a spoon in it
Shine a torch on an object or on the wall and discuss the light by asking questions, such as: 11)
- How does light help us to see?
- How does light travel and how far does it travel?
- What is a shadow?
Session 2 - Resource Sheet 2 - Lesson steps Page 27
Darken the room. Ask students to cover their eyes with their hands to exclude as much light as possible. Ask students to think about a place without light and ask questions, such as:
- Can you describe a place that is really dark? (For example, a cave.)
- What could you see?
- How did you feel?
Note: To enable students to experience a totally dark place, teachers might like to create such a place in the classroom by having blankets or sheets for draping over desks or a large table in a corner covered with thick blankets that touch the floor. (A totally dark place is where you cannot see your hand in front of your face.)
This exercise about an imaginary totally dark space is puerile.
Questions Resource Sheet 2 - Page 29
Using the enlarged copy of ‘In the dark’ (Resource sheet 2), record as a tally the students’ responses to each of the statements. Ask one student to record the tally on an A4 copy. Place the large copy on the science chat-board and the A4 copy in the class science journal. 12) What do you think will happen when the boy switches off the light in this room that has no windows? Answer: | Yes | No | Unsure |
- It will be dark in the room and the boy won’t be able to see the owl.
- The boy will see the owl inside the room because the owl is white.
- The boy’s eyes will adjust to the dark and then he will be able to see the owl.
- The boy will only be able to see the owl’s eyes because its eyes will shine in the dark.
- The boy will need a torch or candle to be able to see the owl.
- When the room is dark the boy and the owl will still cast a shadow.
How do we know if the teachers can provide correct answers/explanations for the above?
Session 2 - Page 19
The travelling light show Students:
- compile a list of light sources
- explore how light travels in straight lines
- investigate the size and direction of shadows.
Focus
The Explore phase is designed to provide students with hands-on experiences of the science phenomenon. Students explore ideas, collect evidence, discuss their observations and keep records, such as science journal entries. The Explore phase ensures all students have a shared experience that can be discussed and explained in the Explain phase
Are the prescribed activities engaging/the best we can do?
Formative assessment - Page 20
Explore phase. It involves monitoring students’ developing understanding and giving feedback that extends their learning.
Key lesson outcomes - Page 21
Science -Students will be able to:
- demonstrate how to modify a peek box to see an object
- describe how objects reflect light into our eyes allowing the objects to be seen
- draw a ray diagram to demonstrate that light travels in straight lines
- describe how a shadow is formed by blocking light.
Literacy - Students will be able to:
- represent their thinking by using key vocabulary related to light
- understand the purpose and features of a ray diagram
- discuss observations of light and shadows
- understand the purpose and features of a labelled diagram
- record ideas about light and shadows.
How do we know if the teacher understanding is sufficient for valid/accurate assessment of the above?
Peek Box
Students’ conceptions - Page 22
Some students might think that we see objects because ‘vision’ comes out of our eyes and strikes the object. Another non-scientific idea is that an image comes directly from the object to our eyes. However, it is the light reflecting off the object into our eyes that allows us to see.
When the reflected light reaches our eyes, our brain interprets it as the images we see. Some students might think that shadows are entities independent of light, in other words light allows shadows to be seen, rather than shadows being a result of absence of light. Students might also think that shadows are reflections of dark light. Students might think light on an object ‘triggers’ the production of a shadow that travels from the object onto the wall or floor where it is seen.
Some students might be confused about the difference between shadows and reflections, for example, drawing a face in a drawing of their shadow
Key lesson outcomes - Page 22
Science - Students will be able to:
- demonstrate how to modify a peek box to see an object
- describe how objects reflect light into our eyes allowing the objects to be seen
- draw a ray diagram to demonstrate that light travels in straight lines
- describe how a shadow is formed by blocking light.
Literacy - Students will be able to:
- represent their thinking by using key vocabulary related to light
- understand the purpose and features of a ray diagram
- discuss observations of light and shadows
- understand the purpose and features of a labelled diagram
- record ideas about light and shadows.
Is a 'Peek Box' a well described/recognised scientific or educational device? What evidence exists to persuade the reader that students and teachers be able to use the device to reach valid scientific conclusions about light? Are there better devices/methods to help obtain the stated science and literacy outcomes?
Teacher background information - Page 21 === “We see objects only when light travels from them to our eyes”
: By contrast, many more objects emit/reflect light that travels to our eyes - but we cannot 'see' it without the help of scientific instruments.
“Ray diagrams use lines to show light travelling. The lines are straight because light travels in a straight line. Arrowheads show the direction of travel.” 13)
“Light travels in approximately straight lines. Careful examination shows that near edges, there are changes in the light that can be attributed to the wave properties of light.”
: So, light travels in 'straight lines' and 'approximately straight' lines, and can 'bend' around the edges of objects… All stated within a few sentences of each other, and all without explanation…
The explanation of why shadows have fuzzy edges ('refraction') is not supported by current science (say within the last 200 years). To find out where is the brightest part of a shadow, see: https://www.youtube.com/watch?v=y9c8oZ49pFc
… and we wonder (as in 'Student Conceptions' section) how students become confused?
And more about shadows in general - a little bit more informative than 'peep boxes' perhaps?:
Students’ conceptions
- Some students might think that we see objects because ‘vision’ comes out of our eyes and
strikes the object.
- Another non-scientific idea is that an image comes directly from the object to our eyes. However, it is the light reflecting off the object into our eyes that allows us to see.
- When the reflected light reaches our eyes, our brain interprets it as the images we see.
- Some students might think that shadows are entities independent of light, in other words light allows shadows to be seen, rather than shadows being a result of absence of light.
- Students might also think that shadows are reflections of dark light.
- Students might think light on an object ‘triggers’ the production of a shadow that travels from the object onto the wall or floor where it is seen.
- Some students might be confused about the difference between shadows and reflections, for example, drawing a face in a drawing of their shadow
Session 1 - Page 23
The 'peek box' is not a recognised scientific instrument. There appears to be no scientific method used in the investigation or collection of data about investigation of interaction of light and objects inside a 'peek box'. Instead, students are asked to refelct on 'Things I'm not sure about…' Arghhhhhhhhhhh….
The concept of 'Ray diagram' is introduced an a diagram labelled 'Example of rays drawn to show path of light' is displayed as a model.
Later 14) the exact same diagram is used as an example of how such a ray diagram is evidence of student misconceptions:
Students’ conceptions Many students will draw small lines emerging from a light source, such as a torch or the Sun. These lines are usually short, straight and in all directions. Light does travel in approximately straight lines but does not stop a short distance from the source unless interrupted by matter. Depending on the nature of the source, the light might travel in multiple directions or it might be focused
Lesson steps - Page 26
Review the shadow activities from the previous session by asking students questions, such as:
- What helps us to see?
- What are ray diagrams?
Explain that students will be working in collaborative learning teams to investigate light and shadows. Discuss shadows by asking students questions such as:
- What is a shadow?
- How is a shadow created?
- What do you notice about the shape of the shadow?
- Why do you think shadows change during the day?
- Can we have shadows at night?
Discuss with students that light is needed to create a shadow and that light can emanate from different sources.
Compile a list of different light sources. (This could be done as a class or a collaborative learning activity.)
The 'Diagram of a shadow formation' and 'Using a labelled diagram to represent shadow formation' are only 'approximately' correct. There is no consistent criteria used to compare 'correct', 'approximately correct' and 'incorrect'. This adds to confusion/misconception.
Some of the latter activities have more value, but all more or less suffer from being boring, confusing, and out-dated.
See the opening summary and foreword at head of this document
AND SO ON…
Appendix
HINT: Add milk powder to water to diffuse more easily see rays of light
Misconceptions - As Highlighted By Third Parties
Source : http://amasci.com/miscon/opphys.html
Light:
Light is associated only with either a source or its effects. Light is not considered to exist independently in space; and hence, light is not conceived of as “travelling”.
An object is “seen” because light shines o it. Light is a necessary condition for seeing an object and the eye.
Lines drawn outward from a light bulb represent the “glow” surrounding the bulb.
A shadow is something that exists on its own. Light pushes the shadow away from the object to the wall or the ground and is thought of as a “dark ” reflection of the object.
Light is not necessarily conserved. It may disappear or be intensified.
Light from a bulb only extends outward a certain distance, and then stops. How far it extends depends on the brightness of the bulb.
The effects of light are instantaneous. Light does not travel with a finite speed.
A mirror reverses everything.
For an observer to see the mirror image of an object, either the object must be directly in front of the mirror, or if not directly in front, then the object must be along the observer's line of sight to the mirror. The position of the observer is no t important in determining whether the mirror image can be seen.
An observer can see more of his image by moving further back from the mirror.
The mirror image of an object is located on the surface of the mirror. The image is often thought of as a picture on a flat surface.
The way a mirror works is as follows: The image first goes from the object to the mirror surface. Then the observer either sees the image on the mirror surface of the image reflects off the mirror and goes into the observer's eye.
Light reflects from a shiny surface in an arbitrary manner.
Light is reflected from smooth mirror surfaces but not from non-shiny surfaces.
Curved mirrors make everything distorted.
Light shines on a translucent material and illuminates it so it can be seen. Light does not travel from the translucent material to the eye.
Light always passes straight through a transparent material without changing direction.
When an object is viewed through a transparent solid or liquid material the object is seen exactly where it is located.
Students will often think about how a lens forms an image of a self-luminous object in the following way. They envision that a “potential image” which carries information about the object leaves the self-luminous object and travels through the space to the lens. When passing through the lens, the “potential image” is turned upside down and may be changed in size.
When sketching a diagram to show how a lens forms an image of an object, only those light rays are drawn which leave the object in straight parallel lines.
Blocking part of the lens surface would block the corresponding part of the image.
The purpose of the screen is to capture the image so that it can be seen. The screen is necessary for the image to be formed. Without a screen there is no image.
An image can be seen on the screen regardless of where the screen is placed relative to the lens. To see a larger image on the screen, the screen should be moved further back.
An image is always formed at the focal point of the lens.
The size of the image depends on the size (diameter) of the lens.
When a wave moves through a medium, particles of the medium move along with the wave.
Gamma rays, x-rays, ultraviolet light, visible light, infrared light, microwaves and radio waves are all very different entities.
When two pulses, travelling in opposite directions along a spring or rope meet, they bounce off each other and go back in the opposite direction.
Colors appearing in soap films are the same colors that appear in a rainbow.
Polaroid sunglasses are just dark glass or dark plastic.
- What can you see?
- How do we know the light is there?
- What happens when you try to hold the light?
- How could you change the light?
Why not create this and all other resource sheets as Google forms?