A good place to start to understand what chess is all about, whether your children are ready for chess, and what you can expect from them is with Jean Piaget's Theory of Cognitive Development.

Piaget put forward the theory that children go through four stages of development. The first stage, which he called the Sensorimotor Stage (up to age 2) need not concern us.

The Pre-Operational Stage (ages 2 to 7) comes next. Piaget claimed that children at this stage of development do not yet understand concrete logic and cannot mentally manipulate information. As chess is very much about concrete logic and mental manipulation of information I would suggest that there's not a lot of point in children of this age doing much chess. If you're keen for your children to learn you might want to teach them the names of the pieces, how to set up the board, and perhaps the moves of the simpler pieces (rook, bishop, queen). Many schools encourage chess for children at this stage of development but it's something with which I cannot agree. Children will be able to learn some, or perhaps all the moves at this stage but they will not be able to do much more than play random moves. All children enjoy playing games and using simple strategy games to introduce the concept of logic to young children is great. Chess is too complex to be used in this way but there are mini-games using subsets of the pieces and rules which can, if you want, be used in this way.

The third stage, the Concrete Operational Stage, covers the junior school years (ages 7 to 11). According to Wikipedia: "The concrete operational stage is the third of four stages from Piaget's theory of cognitive development. This stage, which follows the preoperational stage, occurs between the ages of seven and 11 years, and is characterized by the appropriate use of logic. During this stage, a child's thought processes become more mature and "adult like". They start solving problems in a more logical fashion. Abstract, hypothetical thinking has not yet developed, and children can only solve problems that apply to concrete events or objects. Piaget determined that children are able to incorporate inductive reasoning. Inductive reasoning involves drawing inferences from observations in order to make a generalization. In contrast, children struggle with deductive reasoning, which involves using a generalized principle in order to try to predict the outcome of an event. Children in this stage commonly experience difficulties with figuring out logic in their heads. For example, a child will understand that "A is more than B" and "B is more than C". However, when asked "is A more than C?", the child might not be able to logically figure the question out in their heads."

Children at this stage of development will be able to play chess using simple logic. They'll be able to give a logical reason for playing a move (although the logic may well be flawed) but they will find it hard to think ahead and to consider alternatives. They will be able to play competitive chess at junior level but will struggle with competitive chess at adult level.

Piaget's final stage, the Formal Operational Stage, is essentially secondary school education and beyond. Wikipedia again: "Intelligence is demonstrated through the logical use of symbols related to abstract concepts. At this point, the person is capable of hypothetical and deductive reasoning. During this time, people develop the ability to think about abstract concepts. Piaget stated that "hypothetico-deductive reasoning" becomes important during the formal operational stage. This type of thinking involves hypothetical situations and is often required in science and mathematics. Abstract thought emerges during the formal operational stage. Children tend to think very concretely and specifically in earlier stages, and begin to consider possible outcomes and consequences of actions. Metacognition, the capacity for "thinking about thinking" that allows adolescents and adults to reason about their thought processes and monitor them. Problem-solving is demonstrated when children use trial-and-error to solve problems. The ability to systematically solve a problem in a logical and methodical way emerges."

This, to my mind, is what chess is all about. Children can only really play chess when they reach this stage of cognitive development. This is why I'm sceptical about the value of encourage mass participation in competitive chess by young children.

Having said this, the ages given by Piaget are only averages. I've met children who have been able to play chess to a very high level at the age of 7. These children, though, are the potential top grandmasters with an exceptional talent for the game.

If you're reading this because you think your children might have a talent for chess it may well be that their development is cognitively advanced and they might be able to reach their targets a year or two younger than Piaget might suggest.

Source: http://en.wikipedia.org/wiki/Piaget's_theory_of_cognitive_development