Free preschool for needy kids. Studies show that investing in these kids will pay for itself.

https://eric.ed.gov/?id=ed366433

"Study findings at age 27 as reported in these chapters indicate that the preschool participants have significantly higher earnings, rates of home ownership, and levels of schooling, as well as significantly fewer arrests and social service interventions, than a control group of non-preschool participants. Cost-benefit analysis revealed that, over the lifetimes of the participants, the preschool program returned to the public an estimated $7.16 for every dollar spent."

Even at age 40 (2005) in a 2010 report.

https://highscope.org/perrypreschoolstudy

"The study found that adults at age 40 who underwent the preschool program had higher earnings, committed fewer crimes; were more likely to hold a job, and were more likely to have graduated from high school than adults who did not have a preschool education."