This week Hillary Clinton was in Virginia to talk about women, family and workplace issues. She met at the Mug'n Muffin coffee shop with local participants in a program called Home Instruction for Parents of Preschool Youngsters.

In HIPPY, as it's called, parents receive free books, educational materials and weekly home visits to coach them on how to get their young children ready for school. For example, by reading to them daily.

THE CLAIM:

A Clinton campaign video features Bill Clinton, in a speech, crediting his wife with bringing the program to the U.S. from Israel when she was first lady of Arkansas in 1985.

"She comes in one day, jumping up and down happy," the former president says in the video. "She says, 'I found it. A preschool program in Israel that teaches people to be their children's first teachers even if they're illiterate. I think it could work here' ... Next thing you know it's in 26 states. It's still thriving and there are thousands of people in this country today who have better lives and learn more and grew up just because of her."

THE SHORT ANSWER:

Hillary Clinton did bring the program to Arkansas, but she wasn't responsible for importing it to the United States.

And it is national, in 21 — not 26 — states and DC, but it's not very big — only 15,000 participants each year.

THE LONG ANSWER:

"Clinton discovered the program many years ago when it came to the U.S." says Margie Margolies, the chairwoman of HIPPY USA's board (No relation to Marjorie Margolies, Chelsea Clinton's mother-in-law). "She was instrumental in growing the program in Arkansas when Bill was governor. She had been working for a way to boost the educational start of children in Arkansas, so she reached out to the Israeli founder to find out how to scale it up. Arkansas is still one of our largest programs."

Could HIPPY scale up nationwide? Should it?

Decades of independent research, including randomized controlled trials, show that children ages 3, 4, and 5 who participate in HIPPY are more prepared for school. Studies in four states found that higher reading, math and social studies scores persisted into third, fifth and sixth grades.

Teachers report that parents who participate in HIPPY become more involved in their children's educations for years to come. HIPPY seems to blunt the impact on school performance of factors like being an English-language learner. Children who go through the program also seem to have better attendance, behavior, peer interactions and academic self-esteem.

Although Margolies says that she wouldn't want to "pit" HIPPY against universal pre-K programs, the fact remains that the home-visit program seems to produce similar effects on kids at a lower cost per participant. And there are ancillary benefits, like connecting families to housing, health care and job assistance.

Of course, it's hard to control for the enthusiasm factor. Low-income, working parents who are willing to sign up for 30 straight weeks of home visits, and then actually stick with the program (with no payments or other incentives beyond a few free books), must be exceptionally committed to their children's welfare.

But, if nothing else, the success of HIPPY demonstrates that it is possible to close the notorious " word gap" and change parents' behavior.

"It really makes a huge difference in people's lives," says Margolies, who has been with the program in Milwaukee for nearly two decades. "I'm lucky enough to have seen in many years how much more confidence the parents have."

Copyright 2016 NPR. To see more, visit http://www.npr.org/.