Kindergarten is for 5-year-olds, as everyone knows. Except that many kindergartners turn 6 during the school year, and thousands start at age 4.

Like other states, North Carolina regulates the age of kindergartners in public schools by requiring them to turn 5 by a certain date -- Oct. 16 of the year they enroll.

No matter when the cutoff fell, many parents would face a difficult choice about sending children barely old enough.

But coming almost two months after school starts, North Carolina's date makes the decision harder, some lawmakers and parents say.

Should we let our child start school with mostly older children, and hope she catches up, they wonder? Hold him back a year to make sure he's mature enough?

Advancing the birthday cutoff date would schedule the choice closer to when school starts, an idea state lawmakers are starting to talk about.

To improve kindergarten and to discourage children from falling behind -- and staying behind all the way through high school -- some lawmakers favor barring more 4-year-olds from kindergarten in North Carolina's public schools, starting two years from now.

To attend public-school kindergarten in the fall of 2008, children would have to turn 5 by Aug. 31 of that year. Most schools open Aug. 25.

"You have some children who are barely toilet-trained in the same classrooms with children approaching 7 years old," said state Rep. Louis Pate Jr., a Republican from Mount Olive. "The cognitive differences can be significant."

Pate, who champions the idea of changing the date, said he has learned about the problem from his wife, Joyce, a Wayne County kindergarten teacher.

"Kindergarten is not socializing and learning how to get along anymore," he said. "It's pretty rigorous work. We want children who are ready to learn."

Nobody has to go to kindergarten. School principals decide whether 7-year-old students who don't go to kindergarten should be placed in a first-grade class or in kindergarten.

Goals and trade-offs

Ultimately, Pate said, the effort's aim is to reduce high school drop-out rates by preventing younger students from lagging throughout their school years.

The new rule would have exceptions: Academically gifted children still could get a head start. So could 4-year-olds who have completed preschool.

Only four states have later birthday cutoff dates than North Carolina, the Associated Press has reported. Nineteen have a Sept. 1 cutoff.

If the proposed change in North Carolina becomes law, supporters say, it would improve children's education.

At the same time, they concede, it would force some parents to pay for another year of day care or preschool.

And the move could delay schooling for some of the state's poorest children, who often benefit from an early start.

Supporters say scientific studies back the shift, but some education experts disagree.

"There's not a lot of evidence to suggest that moving up the date would enhance achievement," said Carolyn Cobb, director of the state's More At Four pre-kindergarten program for disadvantaged children. "Sure, children would be more mature if they come in a year older. They might do a little better up-front. But it's not clear that the gains maintain. It's going to require more study."

No evidence shows conclusively whether earlier kindergarten age cutoffs improve high school graduation rates either, she said.

"That might be a wish," she said, "but there's no research one way or the other."

Teachers' anecdotes, however, seem to run in favor of moving the kindergarten age cutoff earlier.

State Rep. Earline Parmon, a Winston-Salem Democrat and former school administrator, said teachers across the state have told her that letting 4-year-olds into kindergarten has long concerned them.

"In many cases, children who enter kindergarten at 4 years old are less mature than the 5-year-olds," she said. "We think this will help students be able to compete better with their peers."

Out of necessity, such generalities often form the basis of public policy. But often they don't hold true for individual children and their families.

Families' choices

Parents such as Laura and Mark Gunter of Raleigh, whose daughter Sloane turns 5 on Oct. 1, wrestle every year with whether to send their fall babies to school.

The Gunters have decided to let Sloane start kindergarten this fall at Lacy Elementary School off Raleigh's Lake Boone Trail, where her older brother Graham, 6, already is a student.

"It came down to us feeling like she's ready," said Mrs. Gunter, a part-time real-estate agent. "She has always held her own with older kids."

Making the start of school the cutoff for turning 5 probably makes the most sense overall, Gunter said, but it's not obviously the right solution for everyone.

"Someday my daughter will be 14, in school with kids turning 16," she said. "She'll be the last one to drive. But people I know who have held their kids back have told me, 'You know, they're not progressing.' "

The cutoff proposal might not progress much, either.

For the idea to advance this year, lawmakers have to bend their rules against taking up new issues unrelated to the state's budget in their even-year "short sessions." The House did that Tuesday, passing a resolution allowing the introduction soon of a bill to make the change.

The state Senate, which hasn't yet considered that resolution, would have to go along with it before the bill's merits could be debated, first in committees.

"There's no telling whether or not they'll bring it up this session," said Tony Caravano, spokesman for Senate leader Marc Basnight, a Manteo Democrat. "There are probably a million bills that people would like to have brought up."