Despite the gridlock that has become synonymous with the nation’s capital, in 2008 Washington, D.C., enacted something groundbreaking. It rolled out universal free access to preschool and pre-k across the city. Just over a decade later, the district offers a roadmap and improvement model for other cities looking to provide universal early childhood access to more families. Here are three key lessons: Lesson 1: Access to early childhood education sets students on a strong learning path. The research is…