Lesson Plan

Explore light and how it can be seen from a distance

01_08_06

Learning Outcomes

Explain why light is harder to see at a distance.

Higher: I can explain that the beam spreads out from the source.
Middle: I can describe that light gets fainter when the source is further away.
Lower: I know that light is harder to see from a distance.

Investigate what happens to light the further I am away from the source.

Higher: I can form a conclusion from what you see.
Middle: I can take accurate measurements.
Lower: I can set up an experiment to see how the size of a beam changes.

Activities

Mission Starter - Engage

Method:

How far do you think you can see with your eyes alone?

Extend the conversation further, asking what we need to see further away - glasses, microscope, telescope, etc.

Resources:

Presentation - starter slide.

The Story - Explore and Explain

Method:

Light Sources Challenge - With your talk partner, describe a light source without saying it's name. Can your partner guess what light source you are describing?

Literacy Challenge - Can you think of words to do with light, which begin with each letter of the word LIGHT?

Answer questions and take part in activities during the presentation.

Stop the presentation at the relevant slides: Talk Partners; AfLs; Songs.

Take part in the Choral Response Questions activity (see Assessment section) after the Keywords/Rocket Words slide.

Resources:

Presentation

Mission Expert - Explain

Method:

Mike Linley talks about how light travels over huge distances.

Resources:

Presentation - expert film

Mission Assignment - Elaborate

Method:

Far Out Light!
Watch today's mission assignment film to help with this activity.  

Ask the children to get into groups of 2. Use a large piece of sugar paper and a torch per group. It is best to make sure the room is dark for this activity. 

One child should shine the torch at the sugar paper from 10cm away. Ask the other child to draw a line with a pencil or felt-tip around the area that the light shines on the paper. 

Is it bright or dull? The children can then measure how wide the beam of light is and add their findings to the Handout, then describe the brightness.


Repeat the exercise, but this time get the children to stand a further 50cm away, then ask them where the torch shines on the paper now? Do this a few times.

At what point can't the light be seen anymore?

Stop at a certain point and place various objects between the torch and the paper, around 10cm away. For example, another piece of sugar paper, a transparant sheet, or a glass of water. What happens to the light from the torch now?

Ask the children to think about lights in other ways - what happens the further you get away from the television? Why shouldn't you look directly at the Sun?

Resources:

Torch
Sugar paper
Various 'blocking objects' of different materials e.g. card, cotton wool, transparent film, water etc.

Mission Log - Evaluate

Method:

Complete the Handout by recording the information from today's Mission Assignment.

Quiz

With their talk partners, the children are to go through the quiz at the end of the presentation and answer the questions.

Resources:

Handout

Quiz in presentation

Assessment

Questions to Ask During the Lesson

What happens when you move closer to/further away from a light source?


Describe what happens to the light when it is close to the paper.


Describe what happens as you move further away.


Can you use the words 'brighter' and 'fainter' in a sentence?

Choral Response Questions/ Phrase Suggestions

What happens to light the further away from it you are?

Choral Response Questions/Phrase Suggestions

It gets bigger and fainter

Teacher Mastery

Students’ everyday experiences are in a world surrounded by natural and artificial light sources, e.g. communication and entertainment technology, living and retail spaces and city streetscapes. For a typical Australian household in 2008, nearly 30% of the household electrical energy used is for household lighting. It is rare for students to experience the total and complete darkness achievable in a photographic dark room or a deep cave.

The everyday world of city students is now so perpetually illuminated that for them the presence of light is often taken for granted. The complete absence of light is an extraordinarily unusual experience. For most students ‘darkness’ means experiencing low levels of light rather than no light at all and so they believe their eyes will always adjust, so that even in total darkness they expect to still eventually be able to see.

Many younger students do not accept that light must be reflected from the surface of an object to their eyes for the object to be seen. Most recognise natural and artificial light sources to be emitters of light and many also believe that bright and shiny objects like mirrors are also sources of light. An important reason for this is that students’ conscious experiences of ‘reflection’ are associated with mirrors and other shiny smooth surfaces. Many believe that rough surfaces don’t reflect the light that strikes them because they are not ‘shiny’ and that light stays on the surface of these objects.
 

Curriculum Fields

Enquiry Skills and Approaches

The Australian Curriculum - Sharing observations with others and communicating their experiences

Chinese Compulsory Education Primary School Science

Know the artificial world around you (learn about common tools and know the functions and usage of simple tools using simple materials and simple tools around you to complete simple tasks). Under the guidance of the teacher the child can use a variety of senses and simple tools, and observe the external morphological observed phenomena and objects.