Belief in matching age with grade is based on an outdated assumption that children’s development proceeds automatically with the passage of time. But in deciding when a child enters school, age is not the critical factor. Current research indicates that readiness requires appropriate stimulation and guidance.

Although teachers often observe that older children are more successful in kindergarten and in the first few grades, research demonstrates that these differences usually disappear by grade three. Moreover, some of the youngest score in the highest quartile in reading, math and general knowledge and some of the oldest score in the lowest quartile.

Because of the current emphasis on standardized testing, many teachers teach children in a lock-step. In contrast, good teachers are able to meet the needs and skill levels of a wide range of children. They are able to stimulate, guide and instruct children at their individual levels by supplying extra help or presenting more challenging supplementary materials.

Raising the entry age for kindergarten without offering the opportunity for cognitive, social and motor stimulation for younger children and children from poor families is a false solution. What's far more important is offering developmentally appropriate preschools or extended-day kindergartens where the goal is to prepare all children for first grade.

Better teacher preparation that provides the know-how to accommodate and challenge the range of children in their classes is also key. Smaller class size and educationally diagnostic evaluation methods would help better meet the needs of individual children.