DominoesMany historians believe the game was invented by the Chinese some time around 1100 AD and it eventually arrived in Europe some time during the 18th century. Similarly to the tangram, the earliest mention of dominoes is from the Song dynasty  China found in the text Former Events in Wulin by Zhou Mi (1232–1298). Modern dominoes first appeared in Italy during the 18th century, but how Chinese dominoes developed into the modern game is unknown. Italian missionaries in China may have brought the game to Europe. 



The word “domino” is most likely to be derived from the Latin, dominus (ie. the master of the house). However, the name “domino” is is also used to refer to the carnival costume worn during the Venetian Carnival, often consisting of a black-hooded cloak and a white mask.




domino maskA domino mask (from Latin dominus, “lord”, and Medieval Latin masca, “specter”) is a small, often rounded mask covering only the eyes and the space between them. The masks have seen special prevalence since the 18th century, where they have become traditional wear in particular local manifestations of Carnival, particularly with Venetian Carnival. Domino masks have found their way into a variety of high and popular art forms.  Masks of this type became known as domini because they resembled French priests’ winter hoods, which were white on the inside and black on the outside.




It is is a game played with rectangular “domino” tiles. The domino gaming pieces make up a domino set, sometimes called a deck or pack. The traditional Sino-European domino set consists of 28 dominoes, colloquially nicknamed bones, cards, tiles, tickets, stones, or spinners. Each domino is a rectangular tile with a line dividing its face into two square ends. Each end is marked with a number of spots (also called pips, nips, or dobs) or is blank.





Most domino games are are played by blocking, scoring and drawing. The more familiar game is the “drawing” one. You can play online here (and choose “draw”):




Worry Dolls (Muñeca Quitapena)

Worry Dolls

Worry Dolls are tiny, hand-crafted dolls from Guatemala. The dolls are clothed in traditional Mayan costumes and stand one-half to one inch tall. 

In the dolls’ original Guatemalan tradition, a local legend about the origin of the “Muñeca quitapena” refers to a Mayan princess named Ixmucane. The princess received a special gift from the sun god which would allow her to solve any problem a human could worry about.

Worry Dolls

In traditional and modern times, worry dolls are sold as souvenirs with a Mayan legend. People tell their doll about their sorrows, fears and worries, then hide it under their pillow during the night. After this, the person will literally sleep over the whole thing. At the next morning, all sorrows are said to have been taken away by the worry doll.


The Tangram

TangramThe tangram (Chinese: 七巧板; pinyin: qīqiǎobǎn; literally: “seven boards of skill”) is a dissection puzzle consisting of seven flat shapes, called tans, which are put together to form shapes. They help with visual perception, logic skills, and dexterity.  It is one of my favorite puzzles. I learned Tangram when I worked with the Montessori system when young, and for me it’s a natural, intuitive system to create geometric shapes and forms.

Tangram Pattern

Tangrams for younger children usually involve “pattern cards” where the seven pieces must “fit” on the diagram. Here’s a website where some of these patterns may be downloaded for free:

However, I prefer to provide the tangram “solution” first, when I work with children or patients. This means that the lines are already printed beforehand. This provides more structure for people who are not ready for the abstraction involved in solving the tangram puzzle.  Here are some examples of tangrams “solutions”, that is with the shapes drawn in.

Tangram solutions

After the child or adult gets used to the lines, he/she can work on a pattern card without the lines.


The objective of the puzzle is to form a specific shape (given only an outline or silhouette) using all seven pieces, which may not overlap. It is reputed to have been invented in China during the Song Dynasty (The Song dynasty was an era of Chinese history that began in 960 and continued until 1279), and then carried over to Europe by trading ships in the early 19th century. It became very popular in Europe for a time then, and then again during World War I. 

Convex Tangram

“Fu Traing Wang and Chuan-Chin Hsiung proved in 1942 that there are only thirteen convex tangram configurations (config segment drawn between any two points on the configuration’s edge always pass through the configuration’s interior, i.e., configurations with no recesses in the outline)”-


In a tangram puzzle set there are :
5 isosceles triangles of various sizes (2 large congruent triangles; 1 medium-size right triangle; 2 small congruent triangles).
1 square
1 parallelogram (the only tangram shape that may need to be flipped when forming certain figures).

You can also play online here:

A Spinning Wooden Top

Although I’ve already written a post on tops here, a spinning top is fascinating for me and remarkable because it tends to defy gravity while it is spinning. The basic physics behind all these effects is that a torque is required to rotate an object. The torque is equal to the rate of change of angular momentum. Angular momentum is similar to linear momentum, but it refers to motion in a circular rather than a straight line path.

It may seem like too much of physics and trying to make sense of it. Usually, the torque acting on a spinning top is just due to the weight of the top. If the top is perfectly upright there is no torque acting on it but if it leans sideways then it will tend to fall over due to the torque about the bottom end. It will indeed fall over if it is not spinning. If it is spinning then it does something else. Instead of falling down, it “falls” sideways. That’s the amazing part. The effect is described as precession. I have some bulky tops, but the gyroscope explains this effect better.

Precession is a change in the orientation of the rotational axis of a rotating body. In physics, there are two types of precession: torque-free and torque-induced.

Torque-induced precession (gyroscopic precession) is the phenomenon in which the axis of a spinning object (e.g., a gyroscope) describes a cone in space when an external torque is applied to it. The phenomenon is commonly seen in a spinning toy top, but all rotating objects can undergo precession. If the speed of the rotation and the magnitude of the external torque are constant, the spin axis will move at right angles to the direction that would intuitively result from the external torque. In the case of a toy top, its weight is acting downwards from its center of mass and the normal force (reaction) of the ground is pushing up on it at the point of contact with the support. These two opposite forces produce a torque which causes the top to precess.

Matryoshka Doll

I remember playing with Matryoshka dolls, not so much for their shapes, but for the novelty of opening one by one and finding a different size.
matryoshka doll

A Matryoshka doll, also known as a Russian nesting doll, or Russian doll, refers to a set of wooden dolls of decreasing size placed one inside another. The name “matryoshka”, literally “little matron”, is a diminutive form of Russian female first name “Matryona” or “Matriosha”.

Matryoshka doll


Matryoshkas are used metaphorically, as a design paradigm, known as the “matryoshka principle” or “nested doll principle”. It denotes a recognizable relationship of “object-within-similar-object” that appears in the design of many other natural and crafted objects. 

The onion metaphor is of similar character. If the outer layer is peeled off an onion, a similar onion exists within. This structure is employed by designers in applications such as the layering of clothes or the design of tables, where a smaller table nests within a larger table, and a smaller one within that.







The first Russian nested doll set was made in 1890 by Vasily Zvyozdochkin, a craftsman woodturner.

Sergey Malyutin




However, the first Russian doll set was designed by Sergey Malyutin, who was a folk crafts painter at Abramtsevo.

The original matryoshka set by Zvyozdochkin and Malyutin, 1892

The original matryoshka set by Zvyozdochkin and Malyutin, 1892

Traditionally the outer layer is a woman, dressed in a sarafan, a long and shapeless traditional Russia peasant jumper dress. The figures inside may be of either gender; the smallest, innermost doll is typically a baby turned from a single piece of wood. Much of the artistry is in the painting of each doll, which can be very elaborate. The dolls often follow a theme; the themes may vary, from fairy tale characters to Soviet leaders. The matryoshka dolls are often referred to as “babushka dolls”, “babushka” meaning “grandmother” or “elderly woman”.


A sarafan, is a long, trapeze-shaped traditional Russian jumper dress (pinafore) worn as Russian folk costume by women and girls.



Montessori Toys (or Materials)

Part of the reason I became interested in occupational therapy was because I became certified using the Montessori method, a learning method invented by Maria Montessori, the first Italian woman doctor. Dr. Montessori began working with intellectually disabled children in Rome. From 1900 to 1901, Montessori began to research European educational materials, seeking those which had been used for children with disabilities. Her research led Montessori to the work of two French physicians of the eighteenth and nineteenth centuries: Jean-Marc-Gaspard Itard and Édouard Séguin. Itard is well known in the twenty-first century for his work with the “Wild Boy of Aveyron,” a youth who had been found wandering naked in the forest, presumably abandoned as a very young child and thus spending many years living alone.

Set of Knob-less Cylinders-The child has to organize the cylinders according to color and size, but the cylinders have no knobs

It turns out that from the work of Itard, Montessori was highly inspired to develop a teaching method that could work with a hypothetical “wild” child, in another words, for her, even children without disabilities had an unorganized central nervous system. Also, with Édouard Séguin, who was a French psychologist who studied with Itard and carried on his research, Montessori drew further confirmation of Itard’s ideas, along with a far more specific and organized system for applying it to the everyday education of children with disabilities

Set of Knobbed Cylinders-The child has to place each cylinder in the block, according to size, and using a small knob for grasping.

Working primarily with the blind, Édouard Séguin developed a methodical approach to breaking skills down into small steps, and was highly successful with a carefully developed collection of hands-on educational materials. In the early twenty-first century, Séguin is recognized as the founder of the modern approach to special education. He introduced the first “sensory” materials, still in use today.

Set of Sandpaper Letters


It turns out that language also had a “sensory” approach. Letters were made out of sandpaper so that children could trace them first, before emitting the sound of the vowel or consonant. Children were also blindfolded and then asked to trace the letter with their fingers and identify which letter it was.


The Movable Alphabet


After learning the sandpaper letters, children would go on to use the “Movable Alphabet”, which are simply cutout letters children can hold in their hands, an eventually compose words with them. These same letters are used today in traumatic brain injury clinics in hospitals today. The Montessori “sensorial” method seeks to provide children with “concrete” learning experiences using gross motor skills, before going on to more fine motor tasks such as writing and reading.

The Mystery Bag

Sound Cylinders


The “mystery bag” using the Montessori method, utilizes objects with different textures, so the child spends time using “somatosensory” skills. These are skills that do not rely on vision but on touch and positioning of objects according to similarities and differences.



There are even “Sound Cylinders” that children shake and sound like rattles! They have to be able to discriminate sounds from soft to loud, shaking each cylinder and comparing it with one another.



Dr. Maria Montessori (1870–1952)


So this is why children attending Montessori schools for the first time may think that all the previously shown materials are toys. They may have no idea on how to use them, and rely exclusively on a ‘Montessori’ guide to teach them, step by step. This makes  Montessori schools more expensive because everyone who teaches this method must be trained and certified. Montessori materials can be handmade, but other times they must be ordered. Once children learn how to use the materials, they become highly disciplined and independent, which was a major goal for Dr. Montessori as an educator.





Other Percussion Instruments

These are additional instruments I meant to add as many are still made in Puerto Rico. This is a ratchet (carraca), also called a noisemaker, is actually also an orchestral musical instrument played by percussionists. Operating on the principle of the ratchet device, a gearwheel and a stiff board is mounted on a handle, which rotates freely.The player holds the handle and swings the whole mechanism around



This is  a “Matraca” or “Rattle”, made out of wood and also used as a noise maker, but also as a baby rattle. This one is believed to be from Spain, but some have been found in different countries.




The Chekeré, Sonajero, or Gourd shekere is also a craft that is very popular in P.R.. It is used mainly as a musical percussion instrument, but also as a noisemaker. This one has “camandula” seeds surrounding the gourd which makes it more valuable in the market, as most are being made out out plastic beads. It is of African origin.


Seed Shakers, Bean Rattle String


This another “noisemaker” or “sonajero”. These are made out of empty “algarrobo” seeds (carob seeds) and they have a beautiful, rain-like noise. These are said to have been used for ceremonial purposes by the Taino Indians in the Caribbean.



These are sometimes called “Spirit Drums”, and are now popular in many countries of the world and used by children as noisemakers.



maraca without handle


This is a maraca (or rattle) without a handle. It is carved by hand on a gourd and can be used both as a percussion instrument or as a noisemaker.