Title of the activity

Subject

Keywords

Learning outcomes

• Will be able to assess student’s everyday life concepts
• Will be able to explain basic concept of optic (emission, absorption, reflection of light)
• Will be able to develop students understanding of the nature of science
• Will be able to explain functionality of our eyes and a photo sensor (advanced & additional sequence; Step 5)

• Will be able to integrate their everyday life concepts in the laws of physics
• Will be able to differentiate between self-luminous and light-reflecting objects
• Will be able to reproduce the definition of emission, absorption, reflection
• Will be able to explain the role of colour and brightness in the process of reflection
• Will be able to recognize, why we see the colours greyish under low lighting conditions
• Will be able to explain the process of vision
• Will understand, that the mean of observation will affect the findings (advanced & additional sequence)

Transversal skills

Number of participants and target age group

• Plumbing Tube 20-30 cm, ⌀ 3-5 cm
• Plumbing Tube end cap same ⌀
• Crossbar – Stick 12-15 cm, ⌀ 0,8-1 cm
• Driller with matching ⌀ of the stick
• Insulating tape with two colours of high contrast
• Gaffer Tape / any other non-transparent tape
• Thin driller / any other device to make a hole of about 1-2 mm

Construction of the vision tube is possible in many varieties. The one presented is quick to build, more or less cheap and the material is easy to get in any hardware store. By using upcycling material it’s even cheaper. However, it is very important that the material of the tube is thick enough and assembled the way that there is no light entering the tube except through the tiny hole! The materials on the list are referring to a version using plumbing material, the one shown in the picture used upcycling material.

bigger hole for observations

The sun, strong and parallel light, is by far the best source of light. On a cloudy day or at night, old school light bulbs (filament lamps) are to be preferred, as LED or other energy saving lamps produce diffuse light only.

Get to know an easy to build and low-budget hands-on-experiment which gives the opportunity of precise observation, inquiry-based learning and reflection of everyday life concepts. With the exploration of the path of light, emission-reflection-absorption and the experience of total darkness through the Vision Tube one can focus on the teaching of scientific facts and the development of students’s nature of science knowledge at the same time.

Are you keen to find out what happens in total darkness? Is it really possible for colours to turn into grey under low light conditions? What do you need to see things? Find your own answers to all of these questions with the Vision Tube.

• Lecture
• Video
• Illustrations
• Examples
• Visuals

• Questions
• Discussion
• Review
• Test
• Reports
• Exercises

• Practice
• Demonstrations
• Presentations
• Projects
• Role play
• Micro-teach

• Problem solving
• Case Studies
• Critical Incidents
• Discussion
• Questioning
• Test

• Projects
• Problem solving
• Case studies
• Plan development
• Constructing
• Simulation

• Simulations
• Critiques
• Complex case study
• Design/ development
• Product generation
• Producing

As with every hands-on-experiment in a group there is the question of disinfection and social distance needs to be ensured. It would be quite a huge challenge to let the kids make the Vision Tube on their own (at home, or in school, so that every kid has their own tube) as it was already a challenge with teachers to get the tube impermeable to light, which is the key of the whole experiment.

An online setting will lead to a more teacher centred setting (with videos / pictures of the Vision Tube) and will cause quite some impact to the inquiry based learning approach. It would mean to develeop a different concept and need quite some work.

(minutes):

(if applicable)

What teaching aims are you fulfilling with this part of the sequence?

However, there are many ways to make sure students make the following observations. Feel free to adapt.

Students should observe:

• The more light enters the tube, the better the crossbar inside the tube is visible
• Even stray light from a non-self-luminous object will send light into the tube
• If there is no light entering at all, the crossbar inside the tube is invisible
• The colours at the centre of the crossbar are shining brighter, colours at the edge are more greyish due to the amount of light hitting the surface
• At low illumination all colours seem to turn into grey. However: the white/bright surface is much brighter than the coloured/dark
• With strong and directed illumination (e.g. parallel light beams of the sun) the inside surface of the tube appears in the same colour of surface the light shines on. E.g. the sun hits a red surface only, the surface inside the tube gets a red shading

Tips & tricks Make sure the students can observe what is to be observed, but don’t show or explain the result of the observation!

(for teachers)

(for students)

(minutes):

(if applicable)

What teaching aims are you fulfilling with this part of the sequence?

Once again, there are many ways to make sure your students describe the observations accurately. Feel free to adapt the concept of the worksheet. However, focus in this sequence on the following steps:

• Depending on the lab-skills of your students, they can work on their own, in small groups, or more teacher focused set up
• Help them to find a precise wording of the observations
• Make sure they can discuss their opinion before they are confronted with the “perfect” scientifically correct wording
• Double check if their observation is based on good exploration vs. everyday life concepts

Tips & tricks: Train their scientific language as much as possible. Make them feel that their everyday life language is not wrong but can be misunderstood for scientific purposes!

(for students)

(minutes):

(if applicable)

What teaching aims are you fulfilling with this part of the sequence?

Your students should be able to explain …

• that the amount of light entering the tube affects the visibility of its inside
• the difference of “shining by itself” and “shining through reflection of light”
• difference between dark and bright surfaces
• the source for an visual impression
• the difference between surfaces of different colours in terms the reflection/absorption of light

Tips & tricks: Try to connect the explanations to the experience with the Vision Tube; if some explanations contradict science, try to falsify them with the Vision Tube or other empirical based examples.

(for students)

(minutes):

(if applicable)

What teaching aims are you fulfilling with this part of the sequence?

The outcome of this Sequence should focus on

• The path of light, from the source, over the different objects to the eyes.
• Defining the terms self-luminous and light-reflecting objects by stating examples from the experiment and everyday life.
• The definition of the essential terms: emission, absorption and reflection of light
• The role of colour and brightness in the process of reflection, to be precise reemission & absorption
• Does the eyesight depend on an active beam sent out from the eyes, scanning all the visible objects or is it more likely that our eyes are passive and need to receive light from all visible objects? => Sender-Receiver Concept

Tips & tricks: It can be a challenge to let the student come up with satisfying definitions and principles. However, this is at the core of transversal skills. With some training and patience, they are able to achieve well.

(minutes):

(if applicable)

The main point of this sequence is to show that the mean of observation has some impact on your result and science is based on a very complex network of different conclusions.

Electromagnetic waves are huge in range, impact and importance. What we see is a tiny bit of it. However, our eyesight is one of our main sources to our understanding of the world and nature. What are the limits of knowledge, when we have only access to information determined by our physical constitution? The invention of the telescope and microscope had a huge impact on science. But can we rely on external objects? Aren’t they some sort of black box, do we really know what they measure? What about a theory proved one million times like the Newtonian laws, are they to be taken for granted?

When we observe through our eyes, we have access to the information which is accessible to the two different kinds of receptor cells of our retina. The type in charge of the colours (cone cells, three different photoreceptor cells for colour) are less light sensitive than the one in charge of the perception of brightness (rod cells, low-light photoreceptor). On the other side, the photosensor of a camera is only referring to three different colours and within a wider spectrum of the electromagnetic field. Moreover, it has much more technical options through different sizes of lenses, exposure time etc.

The aim of this sequence is to sensitize the students to the impact of the mean of observation due to our scientific results and conclusions. It is based on the comparison of two different research groups with contradicting answers to the same question: Can the colours disappear in the dark? Both research groups tested the vision tube under the condition of stray light (only a little amount of light gets indirect through the tiny hole). Group A, the Survey, states that 94 % of the interviewees stated that the colours of the cross bar are appearing in different shades of grey only. Research Group B, the Photograph, states: after getting the right settings (low shutter speed etc) the picture shows the colours of the cross bar very clear, only in lower intensity then outside of the vision tube.

The pupils are then given two sets of explanations of contradictory statements per group of researchers (worksheet attached). The explanations consider logical but science contradicting everyday life concepts,

as well. Moreover, statements in respect to the nature of science and the appropriate scientific explanations at their level of understanding. First, they should discuss the statements in small groups, and try to find out which research group states the true explanation.

The clue is, that both research groups are stating a true, better to say scientifically widely accepted statement. The different outcome is due to different means of observation and the combination of both outcomes is getting us closer to the laws of science.

Tips&tricks: This is a very tricky but high potential learning sequence. Feel free to adapt this idea due to your needs. Lower the challenge by sharing more information or make a teacher centred key lesson out of it.