Keeping up with kindergarten

It's that time of year. Pencils are sharpened, outfits carefully chosen. Facebook feeds are crammed with photos of smiling kids in backpacks. But look closer at the kindergartners -- some are a little older than their peers.

In 2012, 60 Minutes investigated a growing trend known as kindergarten "redshirting," in which parents hold their 5-year-old children back from school until age 6, so they can have an edge on their classmates. The full story is available in the video player above.

"We wanted to give him that extra year of growth for both size for later on, as well as maturity for him," explained Megan Hoffecker, who sent her son to kindergarten at age 6. "I would prefer him to be an older in the class and become a leader in his environment, rather than a younger and be more of a follower."

But isn't that gaming the system? Maybe, but more and more parents are doing it. In 2012, nearly a quarter of some kindergarten classrooms were populated by 6-year-olds. Kindergarten redshirting had more than tripled since the 1970s.

Author Malcolm Gladwell's research for the book "Outliers" is often cited as proof that age matters. "The kids who are born closest to the cutoff date, who are, relatively speaking, the eldest in their class, have a small but not insignificant advantage," Gladwell told Safer, "not just in first grade, but throughout their schooling history."

Samuel Meisels, president of Chicago's Erikson Institute, disagrees. "I think that as children get older, whatever advantage is conferred by starting school a year older decreases dramatically," he said.

Whether or not it works, some critics say it sends the wrong message. Morley Safer is one of them.

"I was totally surprised by the parents in this story," Safer told 60 Minutes Overtime Editor Ann Silvio. "Everything is a competition. There's constant pressure to win. The constant pressure of the scoreboard of life for a 4-, 5- or 6-year-old is, I just think, madness."