Parents, what I'm about to tell you might blow your mind.

The "Summer Slide" — that idea that kids lose a month or two of learning in the summer if they don't practice reading and math — probably isn't real.

Yet, since the 1980s when the first research about this came out, we've been told that our kids come back to school in August knowing less than what they knew in May and it takes them a while to catch up.

Libraries, school districts, bookstores have all created programs around this idea.

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Yet, when Associated Professor at the LBJ School of Public Affairs at the University of Texas Paul von Hippel tried to replicate the 1980s and 1990s studies using data from newer educational tests, he couldn't do it. Hippel studies education policy and evaluates programs using statistics.

"I was a big believer in summer learning," he says. He was until the new data didn't back up the slide that we thought it was preventing.

"It's not that researchers were being deceitful," he says. "The tests they were looking at made it seem that it was true."

Those earlier tests had problems with them, von Hippel says.

In his research, the newer tests couldn't agree with how much learning kids lose in the summer, or how much time it took to regain that knowledge. They were all over the place in their results, he says.

Newer tests and new research find that gaps in education do occur, but they actually happen before age 5, and are not related to the school year, but related to parents' education levels and the family's socioeconomic status.

"Inequality begins at home," he says. "The first five years are the most important."

Kids, he says, are not a blank slate when they enter kindergarten. They already have knowledge; the difference is how much knowledge.

Where we should be concentrating is on programs to help the next generation of parents get through high school and college, he says. That's where countries like Chile have had success, von Hippel says.

Of course, we also can work on early childhood intervention programs as well.

Does this new research mean that we should abandon all the summer reading programs we have been doing?

"They are well-intentioned," he says, but "there needs to be appropriate expectations about what these can accomplish."

Instead of a one-week, or a multiple-week program over one summer in which many of the students for which the program is intended don't show up, it needs to be done during multiple summers and with regular attendance, he says. Then the achievement gap can decrease.

The other struggle is that a lot of the less formal one-week camps or library programs tend to attract kids who are children of educated mothers, he says. If that program didn't exist, those parents are more likely to incorporate reading and learning in regular summer activities.

For parents, von Hippel has this advice:

"You should read to children in the summer," von Hippel says, "but it's not clear  children lose that much knowledge."

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