Kindergarten (search) is not just about play time, snack time and nap time. That was old school.

New-school kindergarten is more academically challenging. Ohio and some other states have recently changed their curriculum and added standards for the early grade in order to prepare students for standardized tests – due in part to the No Child Left Behind Act (search).

"Well ... there's great pressure on educators. There's an even greater pressure on children to achieve as they go through school. Testing begins in the third grade and then continues through the course of a child's academic life," said Mark Ginsberg of the National Association for the Education of Young Children.

Some, however, argue 5- and 6-year-olds are ready for the wake-up call.

"What we know particularly about the research around, particularly, brain development, is telling us that we ... kids at this age are extremely capable,” said Dr. Jane Wiechel of the Ohio Department of Education. β€œIn fact ... we have probably for a long time been underestimating their capabilities."

Click in the box near the top of the story to watch a report by FOX News' Steve Brown.