Extreme Science: Penny Shine

What you will need:

  • Optical illusions printout
  • Scissors
  • Adult supervision


Print the optical illusions (included below) and cut them out as instructed.

Follow specific instructions (below) for each optical illusion image.

What is going on?

An optical illusion is something that tricks your brain.  Many times, the background is just as important in creating an optical illusion as the main image itself.  In other words, it is the relationship between the main image and the background image that tricks your brain into thinking that you are seeing something different.  For example, in the picture below, the car that is farthest away appears to be much larger than the car that is the closest.  This is because of the fact that the background image is something that we are used to seeing.  Notice how everything gets smaller the farther away it is in the picture such as the buildings and the light poles.  In real life, the cars would also appear smaller the farther away they are.  This image, on the other hand has been altered and the cars are actually all the same size.  Due to the relationship to the background the car that is farther away now appears to be much larger that the other two.  Try printing this page (2 copies) and cut the first car out and place it over the other two on your second printout to verify that they are all the same size.

Try this:

  1. Print and cut out the blue and green shapes below.  As you place them on the table, you will notice that the shape that is on top seems smaller than the one on the bottom even though they are exactly the same size.  This is because the top edge is longer than the bottom edge.  By placing one above the other, you are now comparing two DIFFERENT size edges making one of them appear smaller than the other.
  2. Again, print and cut out the images below.  By placing the black shape over the light blue side of each “cube” shape below, you will see that they are both exactly the same size.

  3. Print this last one on a full sheet of paper (please find template for printing below this instruction and illustrations).  Then, cut it into strips (the same size) in the opposite direction of the black lines as shown:

    You will find that if you now lay each strip next to each other so that the solid black lines do not line up, each strip will appear that they are wider at one end.  Simply slide each strip back into alignment and they will once again look like they are all the same size on each end.


Radical Rick

Extreme Science



Recommended for you