Bright Lights, Big Science

What To Do

Activity Prep

• Set up the overhead projector for the Transmission of Light Demonstration.
• Print Bright Lights, Big Science worksheet (1 per participant), Create a Shadow worksheet (1 per participant), and Light wordsearch (1 per participant, optional). 
• Prepare the maze walls ahead of time so they can see an example. Tape the maze mat to the table.
  • Attach two large binder clips to each wall. Each binder clip should have one arm extended (touching the floor) and one arm folded up (touching the wall) for stability. 
  • Place the walls along the lines drawn on the maze mat. 
  • Place the flashlight and light bulb picture where marked. 

Introduction

• Discuss sources of light by placing pictures or writing a list on the board.

Note: Each activity includes a demonstration to introduce the theory. If stations are set up, do all the applicable demonstrations as part of the workshop introduction before allowing students to do any activities. Otherwise, do the demonstrations as a transition between each activity. 

Part 1: Absorption 

Transmission of Light Demonstration

• Put the picture of a fish (on acetate) on the overhead and cover it with a petri dish. Add a bit of water to the petri dish. 
• Explain what transparent means and ask for examples of transparent objects in the classroom.
• Add food colouring to the water. Did this change the view of the fish?
• Discuss examples of coloured transparent objects. 
• Mix some cornstarch and water in another Petri dish and place it over the fish on the overhead. Can you still see the fish? 
• Explain what opaque means. 
• Mix a very small amount of cornstarch and water in a petri dish. Can you still see the fish? 
• Explain what translucent means.
• Discuss examples of translucent objects in the classroom. 

Activity 1a: Transmission of Light

• Set out the frames with various materials, flashlights and Let’s Talk Science logos.
• Participants will make a predictions on whether the following materials are transparent, opaque or translucent:
  • Acetate 
  • Screen 
  • Tissue paper
  • Cardboard
  • Non-glare Plexiglas
  • Aluminum foil 
  • Plastic bag
  • White paper 
• They will test the materials by shining a flashlight on the material to see if they can see the Let’s Talk Science logo on the other side. 
• They will record their answers on the worksheet.

Activity 1b: Shadows 

• Set out pictures of shadows, various objects and flashlights.
• Participants will place an object upright on the X beside the picture of a shadow (using a piece of plasticine to hold it in place).
• They will use a flashlight to recreate the shadow picture. 
  • They may have to adjust the position and angle of the flashlight in order to recreate the shadow. 

Part 2: Mirror Maze

• Explain reflection and discuss examples of places/things that are reflective. 

Reflection Demonstration 1

• Have a volunteer stand at the front of the class. They must keep their eyes facing straight ahead. 
• Ask them how they could use a mirror to see their feet. 
  • Have them try to hold the mirror perpendicular to the floor so that they still can’t see their feet.
• They need to angle the mirror or move it downwards towards their feet.
• Have them track the path of light from the source to their feet up to the mirror and into their eyes.

Reflection Demonstration 2

• Use the ball to demonstrate how light bounces off a mirror.
  • If bounced straight down, it bounces straight back up. 
  • If bounced at an angle, it will bounce back up at an angle in the opposite direction. 

Activity 2a: Mirror Maze

• Working as a team, participants need to arrange the mirrors throughout the maze so that when you shine the light into the maze the light reflects off of the mirrors and shines on the picture of the light bulb at the end. 
• Refer to page 22 of the Bright Lights, Big Science manual for the mirror answer key. 

Activity 2b: Mirror Writing

• Participants will write their name on the worksheet so that when they look at it in the mirror it appears correct.

Part 3: Refraction

Toy Car Demonstration

• Which car would travel faster: the one on a smooth surface or the one on the rough surface? 
  • Have two volunteers or yourself release the cars at the same time. The “ramp” should be on a slight angle so the entire class can see. 
• What would happen if the car moved from a smooth to a rough surface? 
  • Move one car so that it travels in a straight line from the smooth surface to the rough surface. 
• What would happen to the car as it travels on an angle from the smooth surface to the rough surface?
  • Hold the ramp at an angle and move the car so that one of the front wheels hits first and turns the car onto the rough side. Do it in slow motion a few times before releasing the car and having it turn on its own. 

Broken Pencil Demonstration

• Fill a clear cup ¾ full of water and place a pencil in the cup at an angle. 
• Observe the pencil. 
• Explain how refraction makes the pencil look broken. 

Activity 3a: Bending Light

• Set up a flashlight so that its light shines through the paper towel tube towards a comb. Participants will draw the shadow on their worksheet. 
• Afterwards, they will place a glass of coloured water in between the paper towel tube and the comb. They will draw the shadow on their worksheet.
• They will put a lens in between the paper towel tube and the comb (use a ball of Plasticine to keep the lens in place). They will draw the shadows on their worksheet. 

Activity 3b: Magnifying Glasses

• Participants will use a magnifying glass to read the tiny symbols on the cards. 
• They will draw the magnified images in the squares provided on their worksheet. 

Activity 3c: Refraction Viewers

• Participants will use the refraction viewers to see the colours of the rainbow. 

At this point in the workshop, briefly review the topics explored in activities 1-3 and provide explanations for their observations. 

Part 4: Kaleidoscope 

• This activity is to be done as a class. 
• Introduce kaleidoscopes and other optical devices. 
• To build their kaleidoscope, each participant will:
  • Draw a design on the small and large piece of acetate using any colored permanent markers. 
  • Glue a piece of the shiny mylar onto the cardstock. 
  • Fold the cardstock and Mylar along the dotted lines to form a triangular prism with the mylar on the inside. 
  • Tape the prism together along the seam. 
  • Carefully poke a pin through the large acetate in the middle.
  •  Poke the pin through the small acetate in one corner so they are held together with the pin. 
  • Tape the pin and acetate pieces to one end of the tube directly above a point of the prism. 
• They can look through the open end of the tube and point it towards the light and turn the large acetate with their finger.

Wrap-up

• Discuss what they saw when they looked through the kaleidoscope. Explain the two properties of light that create the colours and patterns of the kaleidoscope. 
• Discuss possible careers related to the topics covered and what they would need to do (schooling, experience, etc…) to get into those careers.