Optical Illusions (Age 8)

The Activities

  1. Topic: Volume. Book: Room for Ripley by Murphy. This is a simple book about filling a fish tank with water. It covers the conversions between cups, pints, quarts, gallons.
  2. Topic: Optical Illusions. We did several pages from this really cool optical illusion activity book:



How did it go?

This was the first circle for 4 weeks due to vacations and travelling. We only had two kids this week, which made for a really relaxing, fun circle. Also the optical illusions were really fun, which kept everyone interested.

Broken Lines

First we did a few worksheets where we made lines that did not appear to be straight or seemed to be different lengths, based on the context around the lines. One of the kids had already seen optical illusions before, so she was confident immediately that all were the same length, and refused to be fooled. However, one sheet you had to guess which of 4 parallel lines lined up with a line above, and she guessed incorrectly. So, she did get fooled once.

Ghostly Images


We colored in four high-contrast images, and then stared at the center of each one for 30 seconds. Then we quickly stared into the center of the white circle, to see a ghostly image of what we had just been looking at.

I had not done this one before, and at first it was tough to see the image in the white circle. But one of the kids said she saw it, and so we tried a couple more times, and everyone was able to see.  The tricky thing is the ghostly image is the opposite of the one your stared at, so the black ghost appears as a glowing white ghost. It was really interesting, and unexpected by all, to see what colors the other shapes appeared to be, in the white circle.

The Bird in the Cage

Next we used markers, poster board, and string to make the classic illusion of the bird in the cage.  The two kids were more exciting: one made a lion and a cage, one made a unicorn and a garden.

We tried this illusion two ways. First we tied strings to each side of the circle, then twisted the string up and pulled them straight to make it spin. This really didn’t work very well, and it took two people, and a long time, to twist up the string.

One of the kids said she had done this before by taping a straw to the picture, and spinning it. My daughter didn’t find any straws but she did find a few glowsticks. This method was much more successful.

Time for Tessellations (Age 6)

The Activities

  1. Topics: Logic, Puzzles:  Book: Playful Puzzles for Little Hands, by Taro Gomi.  This is the third time we’ve done puzzles from this book.
  2. Topics: Tesselations, Geometry, Patterns:  Each kid made a square-based tessellation by starting with a 3 inch square of poster-board, drawing an inset on two adjacent sides, cutting it out, and taping to the opposite side.  They each kid filled a 8.5 x 11 sheet of paper with the tessellation and colored it.

    A rather ambitious tessellation

    How Did It Go?

We had three kids this week.  We took it pretty easy this week after the month long break.

Playful Puzzles

This continues to be a great book, lots of interesting fine details in the “What’s different?” puzzles.


I started by showing them how to make a tessellation and how to trace it.  Two of the kids made fairly simple tessellations, one made a very complicated one.  I cut them all out and taped them.  The two kids with easier tessellations started getting distracted and chatting part way through, so all three kids ended up nearly finishing.  Two of the kids picked rainbow colors.