Situation puzzles

Puzzles, situation puzzles and recreational mathematics.

situation puzzles and recreational mathematics. Neuron juice

Neuron juice.

The important thing is not to stop questioning. (Albert Einstein.)


Logic Games

This is a little selection of situation puzzles that you can make by yourself easily and using easy-to-find materials.


The first ones, the Come-Cocon's pyramids series, are really special for me and I recommend you to build them. Their difficulty is progressive ―the more layers the puzzle has, the harder it is to find the solution. That's why you should begin with the first one and then continue adding more rings.




Piramide de come-cocon Piramide de come-cocon II Piramide de come-cocon III Piramide de come-cocon IV
Come-Cocon. Come-Cocon II. Come-Cocon III. Come-Cocon IV.


Puzzle solitario Puzzle cuero Puzzle escalera
Game of solitaire. Leather. Stairs.


Puzzle mosqueton Puzzle columpio
Carabiner Swing.


More situation puzzles at my puzzle collection.


Como poner varios clavos en equilibrio encima de otro

Situation puzzle. Nails in balance.

I bought this situation game some years ago at a street market in Gandia (Valencia) and I hadn't published about it in Neuron Juice yet. Its craftsman signs his puzzles as JcC.

This puzzle is formed by 7 nails and a wooden base that serves as bracket. One of the nails is black although it's just because of aesthetic reasons. The nails can be taken off the base, except the black one that must be nondetachable.

This puzzle is a different one —its objective isn't to assemble or disassemble pieces, nor release a ring, nor arrange pieces. Its objective is to put the movable nails in balance on the black one.








Cruz C.O.C.

Materials: Wood.
Category: Assemble.
Number of pieces: 3.
Difficulty: Medium.



This puzzle's objective is to assemble its three pieces. If we start with the puzzle assembled, it is easy to see the system. However, if we start with the unleashed pieces it becomes harder.

Two of the three pieces are identical and are crosswise, square C-shaped. The other one is crosswise, square O-shaped.





Materials: Wood.
Category: Disassemble.
Number of pieces: 5
Difficulty: Medium.



This puzzle's objective is to disassemble the five pieces that apparently form it.

One of the pieces is the sphere that is the core of the puzzle. Another one is cylinder-shaped. There are two prisms left ―in one of them lies the secret of this puzzle, as it is formed by two pieces that serve as key.

Once the puzzle has been disassembled, assembling it again is a piece of cake.





Materials: Wood.
Category: Disassemble.
Number of pieces: 3 (+4)
Difficulty: Medium.



This puzzle's objective is to release the central frame that surrounds the cross. At first sight it is impossible as there aren't apparently no movable pieces. In order to find them we need to use our sense of hearing ―if we shake slightly the puzzle we can hear a sound in the inside that provides an essential clue to solve the puzzle.




Cruz 3D

Materials: Wood.
Category: Assembling.
Number of pieces: 6
Difficulty: Uncertain.



This puzzle's objective is to assemble the six pieces that form it. If we start with the puzzle assembled, it is easy to see the system. However, if we start with the unleashed pieces it becomes harder.

The puzzle is formed by 6 different pieces. One of them is a prims that serves as key to disassemble the puzzle and to attach the rest of the pieces when it is assembled.





Materials: Wood.
Category: Figures.
Number of pieces: 7
Difficulty: Easy.



Tangram is an antique Chinese puzzle that consists in making forms with all the pieces given. The figures must use all of the pieces without overlapping them. The 7 pieces called Tans, which form a square, are the following:

  • 5 triangles in different sizes
  • 1 square
  • 1 rhomboid parallelogram 

There are several versions about the origin of the word 'Tangram'. One of the most accepted tells that the word was invented by an English man by joining the Cantonese word 'tang' that means 'Chinese' and the Latin word 'gram' that means 'written' or 'graphic'. Another version tells that the origin of the puzzle dates back to between 618 and 907, the period when China was ruled by the Tang Dinasty. therefore the name.

It is very probable that Tangram was created from the Yanjitu furniture set during the Song Dinasty. According to the Chinese record, this furniture was originally formed by a set of 6 rectangular tables. Then a triangular table was added and the tables could be arranged in order to form a big square table. Later there was another variation during the Ming Dinasty, and then it turned into a game.

Tans are usually kept forming a square.

A leyend says that a servant of a Chinese emperor was carrying a really expensive and breakable ceramic mosaic. The servant tripped over and the mosaic tore up. The desperate servant tried to reassemble the mosaic into a square shape, but he couldn't. However, he realized he could make many other figures using the pieces.

It isn't certain who invented the puzzle nor when, as the first Chinese publications where the game appears date back to the 18th century, when the puzzle was already largely known in several countries. In China, Tangram was very popular and considered a game for women and children.

Since the 18th century several translations where published in America and Europe that explained the rules of Tangram. Tha game was called 'the Chinese jigsaw puzzle' and it became so popular that it was played by children and adults, common people and celebrities from the world of science and arts. Napoleon Bonaparte turned into an expert in Tangram since his exile in Saint Helena island.

Regarding the number of figures that can be made using Tangram, most of the European books copied the original Chinese figures, just several hundreds. By 1900 new figures had been invented and the number was approximately 900. Currently about 16,000 different figures can be made using Tangram.

Nowadays Tangram isn't just used for entertainment, it is also used in psychology, design, phylosophy and specially pedagogy. In the field of math teaching, Tangram is used in order to introduce concepts of plane geometry, and to promote the development of children's psychomotor and intellectual abilities as it allows to join playfully materials handling and abstract ideas formation.


Wikipedia contributors. Tangram [online]. Wikipedia, The free encyclopedia, 2007 [date of query: September 9, 2007]. Available at <> [in Spanish].