But in England, the reaction to that research was dramatically different. Just over a decade ago, in 2004, Parliament reviewed the research on the multiple benefits of preschool for 3-year-olds—presented in a multi-year study by Melhuish and his team—and decided only one conclusion could be drawn: The government should pay for preschool for all 3-year-olds. Primary school has started with reception at age 4 for most children for decades, according to Melhuish. In 1998, it became mandatory for primary schools to offer reception, something most were already doing.

The study in question, called Effective Pre-school, Primary and Secondary Education (EPPSE), tracked 3,000 children from the mid-1990s through 2008. The government funded the study and made policy decisions based on its results. Melhuish explained this as if it were unremarkable; he viewed as commonplace a government’s decision to recognize new scientific information and change course accordingly.

The types of academic and developmental gains observed in children in the EPPSE study are very similar to those observed in U.S. studies on the effects of preschool. However, the gains seem to carry through as children continue to later grades, with less “fade-out” than has been observed in the U.S.—a finding Melhuish attributes to better primary schools.

Another reason to offer universal preschool, Bristol’s Jaeckle said, is to preclude the possibility of a stigma attaching to free preschool. There can be no stigma if everyone gets the same service, she pointed out. Low-income families who need the service most don’t have to feel ashamed about enrolling their children in the public program, she argues, because it’s the same program is available to all kids, regardless of their socioeconomic status. That is not a concern commonly heard in the U.S. in regards to the uptake of government services.

But mostly, both Jaeckle and Melhuish argue, it makes sense to offer a universal preschool program because it is the best way to ensure quality, something Head Start, the U.S.’s own federally funded public preschool program, has struggled with. “If you have a system which excludes the middle class, that system is almost doomed to be poor quality,” Melhuish said. “Without the pressures of various kinds—social and political—that the middle class are able to exert because of their social capital, quality of service will not be maintained.”

And though it’s not a common position among lawmakers, some experts in the U.S. have reached the same conclusion: Universal access is the only way to ensure quality.

Right now, whether a parent has access to a high-quality preschool program in the U.S. has more to do with that parent’s education than anything else, said Steven Barnett, the director of the National Institute for Early Education Research, a U.S. think tank. Even parents with graduate degrees have only a one-in-three chance of enrolling their child in a high-quality program, he added. “And that's after 50 years of a policy of targeted preschool,” he said. “I think 50 years is enough. We need to try something different.”

Government data from England is bearing that notion out. By the time English children have finished receptiontheir first year of primary school, 66.3 percent of them have reached a “good level” of development. That includes measures of academic skills like reading, mathematics, and writing as well as measures of non-cognitive skills like self-confidence, imagination, and relationship building. The percentage of children achieving “good development” has increased year over year since the introduction of free preschool 12 years ago. Remember, the age of children attending their first year of primary school in England is typically younger than that of children attending their first year of elementary school in the U.S., so these gains accrue to English children before their American counterparts have even started kindergarten.