Summer is approaching, and that's when parents must make the decision about whether to send little Johnny or Sue to school for the first time.  Some parents want their children to perform better academically; others worry about the social emotional effects of starting a boy before he is ready, or of allowing a child with a summer birthday to be the youngest and smallest in this class.

Many  parents are aware of mandatory testing,  that kindergarten is harder than it used to be, and with educators referring to it as the "new first grade." 

Some also have been influenced by research indicating that boys typically mature at a slower rate than girls in key school readiness areas, such as language and fine motor skills.

About 11% of American boys entered kindergarten a year late in the 1990's, compared with about 6% of girls, according to the most recent national study.  But those figures may now be outdated.

"We've had the No Child Left Behind Act (since 2002), which is really whipping schools to accelerate as much as they can, and making delayed kindergarten entry more attractive," says Leonard Sax, author of "Why Gender Matters: What Parents and Teachers Need to Know About the Emerging Science of Sex Differences."

In his practice as a family physician in affluent Montgomery County, Md., about 1 in 2 boys are starting kindergarten at age 6, compared with 1 in 10 a decade ago. The number of girls starting kindergarten about age 6 or older has gone up to, but from 5 percent in 1970 to a relatively modest 10%  in 2001.

There are fairness and equity issues.  Many parents can't afford the child-care costs involved in delaying kindergarten.

If you can afford to do this, you're really giving your child an advantage.  And, after all, all of our children should be given the greatest advantage.  The children who start kindergarten later may get onto the sports team first or get the parts in the school play.  It would be a good idea if the later starting age would be the same for everyone, as kindergarten has become so demanding, that some kids can't keep up.