Competition is, In general, A contest or rivalry between two or more entities, Organisms, Animals, Individuals, Economic groups or social groups, Etc. , For territory, A niche, For scarce resources, Goods, For mates, For prestige, Recognition, For awards, For group or social status, Or for leadership and profit.  It arises whenever at least two parties strive for a goal which cannot be shared, Where one's gain is the other's loss (an example of which is a zero-sum game). 
Competition occurs naturally between living organisms which co-exist in the same environment.  For example, Animals compete over water supplies, Food, Mates, And other biological resources. Humans usually compete for food and mates, Though when these needs are met deep rivalries often arise over the pursuit of wealth, Power, Prestige, And fame.
Competition is often considered to be the opposite of cooperation, However in the real world, Mixtures of cooperation and competition are the norm.  Optimal strategies to achieve goals are studied in the branch of mathematics known as game theory.
Competition is a fact of life. Kids need to get use to it when the stakes are low because the stakes go up the older you get. Pushing yourself to succeed also makes them perform better. They get better grades. A better chance at college, And a better chance at their future. Look, If you were an employer, Would you rather have the best/better employees or would you be willing to pay the same for ones that may be far worse?
I've seen students suicide because they couldn't get the top place in a test. I've watched, Horror-struck, As my friend- who couldn't stand the pressure- ran away from home. However, The sad truth is, Competition prunes and weeds out weaker beings. We are always straining ourselves to be the best, The one who gets most recognition and privileges. In doing so, We improve more than we ever could have when we have no competition.
Competition, I believe, Is crucial to children's maturity. As it shows them how to handle losses with grace and take wins with pride. And along with that. It also provides healthy fun and a contrast to the peachy "everyone is a winner" attitude that most schools now a day possess.
Without competition a student has no drive to improve, And with that they never get better, So when the real world hits them with not getting into schools or obtaining jobs they wouldn't know how to react, So if a child loses at a youth age, They could either sulk and never improve, Or they could realise they need to be better, And work harder to improve them self and become successful at sports or academics, Or even both
This is so because by chance if a child loses in a competition, He takes it very seriously and gets very tensed and type of depressed which is not good. And thus he doesn't gets interested in his classes either and spends his time thinking about it. So i will go against this overwritten topic