On Tuesday night at the DNC, Bill Clinton took the Philadelphia stage and gave a heartwarming and personal speech about his wife, who’s facing a real charge from Republican nominee Donald Trump. During his speech, Clinton mentioned a preschool educational program, created in Israel, called HIPPY, or Home Instruction Program for Preschool Youngsters, which Hillary championed while her husband was governor of Arkansas, along with other difficult policy changes. (In May, Hillary published an ad relating to the HIPPY program with her husband’s voice as narrator, too). Here’s the former American president at the DNC:

So what is HIPPY, who created it, and for what purpose?

According to this paper published in 1999 in Princeton’s The Future of Children journal, HIPPY is “a two-year home-based early education intervention program designed to help parents with limited formal education prepare their 4- and 5-year-old children for school.” It was brought to the U.S. in 1984 (although The Times of Israel reports that it came to the States in 1980).

The educational program was developed in Israel in 1969 by Dr. Avima Lombard at Hebrew University’s National Council of Jewish Women Research Institute for Innovation in Education, located in Jerusalem.

Based on evidence that some early education intervention programs could help prepare children from low-income families to succeed in school, the program was created to respond to the low educational achievement of immigrant children in Israel. It was grounded in the recognition that the family plays a significant role in young children’s learning. Specifically, HIPPY was developed to prepare children for school by enhancing the home literacy environment, the quality of parent-child verbal interaction, and parents’ ability to help their children learn.

According to The Times of Israel, the program was developed specifically “to help immigrants from North Africa and the Middle East prepare for life in their new country.”

According to Scott Gordon, the interim executive director of HIPPY USA, the first HIPPY program began in Tulsa, Oklahoma, in 1984. Programs were also set up in Richmond, Virginia. In 1985, Hillary Clinton, then the first lady of Arkansas, learned about the program after reading about it in a newspaper in Florida. A year later, the first HIPPY program was set up.

“What [Bill] talked about [during his DNC speech] was from the heart and accurate,” said Gordon, who worked with Hillary Clinton to set up a HIPPY home at the Children’s Hospital in Little Rock in 1991. “It was fun, we had an exciting time.” Now, the Children’s Hospital is home to both the Arkansas HIPPY office, as well as its national office, which operate independently.

There are 140 HIPPY sites in 23 states and Washington, D.C., according to the program’s U.S. website. In Arkansas alone, said Gordon, there are 5,000 families that participate in the educational program. Nationally, he estimates that up to 17,000 families participate.

Gordon retired as executive vice president of the Children’s Hospital in 2014, but said he just couldn’t stay away. “HIPPY’s the one program I would sacrifice the freedom of retirement for,” said Gordon.

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