Among the 43 states that have a publicly funded preschool program, Hawaii ranks last with less than 5% of 4-year-olds enrolled. That's according to a 2017 report from the National Institute for Early Education Research. On Wednesday, Governor David Ige signed a plan that aims to expand access to public pre-k.

During his annual address to lawmakers, Ige laid out his goal for expanding the state’s current public pre-kindergarten program. Only about 520 kids are currently enrolled in state Pre-K. That works out to about 3% of Hawaii’s 18,500 4-year-olds. The governor’s plan would raise that number to almost 7,000 in 10 years’ time.

That has prompted two major questions from lawmakers: “How will you pay for it and where will those new students go?”

To the first, Ige mostly demurred, saying that the expansion would be gradual and funding sources can be identified as growth happens. Regarding classroom space, the governor plans to begin by making some structural changes to the Department of Education’s public-school system to free up space in existing facilities.

But Ige also stated that some 300 new classrooms would need to be added to the current stock, most of them on the neighbor islands.

Pre-K is often lauded as a palliative for many societal problems, including the high-school dropout rate, college enrollment, teen pregnancy, and boosting lifetime earnings. The reality is more complicated.

As states around the country have expanded public Pre-K over the last 15 years, results have been mixed. In jurisdictions that focused on quality, rather than just the number of students enrolled, benefits appear robust. But where expansion of the public option was rushed to implementation, results have shown there can actually be a negative impact.

Experts at the University of Hawaii cautioned that enrollment needs to be accompanied by increase in the number of early childhood education specialists and the development specific Pre-K curriculums for society to really see the benefits.

Hawaii’s current public Pre-K program already preference to at-risk populations like children of low earners, special education students, and speakers of English-as-a-Second Language. That will continue under any new expansion.

Governor Ige’s plan seeks to supplement the existing private preschool system, which currently covers 45% of Hawaii 4-year-olds. His goal is to have 90% of that population enrolled in some form of Pre-K, with the state’s program eventually covering roughly 35% of kids and another 10% being funded through federal programs like Head Start.