http://www.nytimes.com/2011/09/25/opinion/sunday/dont-delay-your-kindergartners-start.htmlDelay Kindergarten at Your Child�s Peril
By SAM WANG and SANDRA AAMODT
New York Times
September 24, 2011
THIS fall, one in 11 kindergarten-age children in the United States will not be going to class. Parents of these children often delay school entry in an attempt to give them a leg up on peers, but this strategy is likely to be counterproductive.
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Teachers may encourage redshirting because more mature children are easier to handle in the classroom and initially produce better test scores than their younger classmates. In a class of 25, the average difference is equivalent to going from 13th place to 11th. This advantage fades by the end of elementary school, though, and disadvantages start to accumulate. In high school, redshirted children are less motivated and perform less well. By adulthood, they are no better off in wages or educational attainment � in fact, their lifetime earnings are reduced by one year.
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Parents who want to give their young children an academic advantage have a powerful tool: school itself. In a large-scale study at 26 Canadian elementary schools, first graders who were young for their year made considerably more progress in reading and math than kindergartners who were old for their year (but just two months younger). In another large study, the youngest fifth-graders scored a little lower than their classmates, but five points higher in verbal I.Q., on average, than fourth-graders of the same age. In other words, school makes children smarter.
The benefits of being younger are even greater for those who skip a grade, an option available to many high-achieving children. Compared with nonskippers of similar talent and motivation, these youngsters pursue advanced degrees and enter professional school more often. Acceleration is a powerful intervention, with effects on achievement that are twice as large as programs for the gifted. Grade-skippers even report more positive social and emotional feelings.
These differences may come from the increased challenges of a demanding environment. Learning is maximized not by getting all the answers right, but by making errors and correcting them quickly. In this respect, children benefit from being close to the limits of their ability. Too low an error rate becomes boring, while too high an error rate is unrewarding. A delay in school entry may therefore still be justified if children are very far behind their peers, leaving a gap too broad for school to allow effective learning.
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The same authors recently wrote the book "Welcome to Your Child's Brain: How the Mind Grows from Conception to College", which may cite research supporting the above claims.
