Today’s Wonder of the Day was inspired by Juan. Juan Wonders, “What is the domino effect” Thanks for WONDERing with us, Juan!

Have you ever played dominoes? Some children like to play games with the black and white rectangles. Others line them up in long rows and then knock them down. Regardless of how you use them, dominoes are fun to play with!

Dominoes are the individual parts of a domino set, which usually contains 28 pieces. They have many nicknames. You may have heard them called bones, cards, tiles, stones, spinners, or tickets.

Each domino is a rectangle divided with a line down its middle. This separates its ends into two squares. Each end is either blank or has a number of spots—called pips. Dominoes are like dice or playing cards in that they can be used to play many different games.

Traditional domino sets have one unique piece for each possible combination of numbers from one to six spots. These sets are often called “double six” sets. Why? The piece with the highest value has six spots on each end. Other sets with more dominoes are available. The largest are “double 18” sets that contain 190 dominoes.

Have you ever WONDERed where the name “dominoes” came from? They’re named for their resemblance to Italian carnival masks, which were called domini. The masks were white with black spots. In turn, they were named after French priests’ hoods that were black on the outside and white on the inside. The name ultimately comes from the Latin word dominus, which means “lord” or “master.”

The most basic game of dominoes requires two players and a “double six” set. The 28 dominoes are first placed face down in a pile. This is called the stock or boneyard. Then, each player chooses seven dominoes.

One player begins the game by playing one of their dominoes. The other player will then try to play one of their own by placing it next to the first domino. The catch is that it has to have an end that matches the same number of pips as one end of the previously-played domino.

What if the second player does not have any dominoes with matching values to the one already played? Then they must choose another domino from the boneyard. They keep doing so until they find a domino that can be played. This pattern continues until either one player wins by playing all of their dominoes or until neither person can play.

Of course, this is just one simple game using dominoes. There are many other possibilities. Some of the games can be very complicated with lots of rules to remember!

Not everyone uses dominoes to play these types of games, though. Many children prefer to use dominoes as toys that they can stack on end in long lines. If spaced properly, the first domino in the line can be tipped over. This causes the next domino in line to tip and so on and so forth. Eventually, all the dominoes topple over!

Very complex designs can be made by stacking dominoes in this way. This also led to the common phrase, the “domino effect.” That describes a series of events that starts with one simple action that ultimately leads to much greater—and sometimes catastrophic—consequences.

Have you ever lined up dominoes to make an interesting shape? Maybe you’ve played one of the many games that are possible. Dominoes are a great example of how some toys stand the test of time!

Standards: CCRA.L.3, CCRA.L.6, CCRA.R.1, CCRA.R.2, CCRA.R.4, CCRA.R.10, CCRA.SL.1

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