Creative Problem Solving

Puzzles and Exercises

Effective Thinking Tests


The problems below are not just brain-teasers: they illustrate principles about
creative thinking, challenging assumptions, and problem solving.



Test 1: The Nine Dots


Connect up the dots by four straight consecutive lines. Don't retrace or lift your pen off the paper.

Excellent result: if you complete the task within three minutes


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Test 2: The Six Matchsticks

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Arrange six matchsticks in a pattern of four equal-sided triangles. You may not break the matchsticks. Find two solutions.

Excellent result: if you find the both solutions within five minutes


Test 3: Who Owns the Zebra?

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  1. There are five houses, each in with a front door of a different color, and inhabited by people of different nationalities, with different pets and drinks. Each person eats a different kind of food.

  2. The Australian lives in the house with the red door.

  3. The Italian owns the dog.

  4. Coffee is drunk in the house with the green door.

  5. The Ukrainian drinks tea.

  6. The house with the green door is immediately to the right (your right) of the house with the ivory door.

  7. The mushroom-eater owns snails.

  8. Apples are eaten in the house with the yellow door.

  9. Milk is drunk in the middle house.

  10. The Norwegian lives in the first house on the left.

  11. The person who eats onions lives in the house next to the person with the fox.

  12. Apples are eaten in the house next to the house where the horse is kept.

  13. The cake-eater drinks orange juice.

  14. The Japanese eats bananas.

  15. The Norwegian lives next to the house with the blue door.

Who drinks water and who owns zebra?

Excellent result: if you find the both answers within 30 minutes.