This study examines the Denver Preschool Program (DPP), a voter-approved sales tax initiative that provides a tuition credit for four-year old children to attend preschool. Using propensity weighting and doubly robust modeling on ten cohorts of kindergartners from 2009–2010 through 2018–2019, we found DPP participants were more likely to read at grade level and less likely to be retained or to be chronically absent than their similarly-situated non-DPP peers. The absolute magnitude of the effect sizes for reading achievement and chronic absenteeism ranged from 0.21 to 0.28, and were considered substantively important. The relationships were stronger for DPP participants who had enrolled in a school-based, pre-kindergarten program than DPP participants who had enrolled in a community-based preschool, and the effect sizes were almost twice as large for pre-kindergarten participants than for community-based participants on reading achievement. Policy implications are discussed. (author abstract)