This report is Part I of the Evaluation and it: - Documents the expansion of 4K and expenditure of funds in Fiscal Years 2014-15 and 2015-16; - Provides 2015-16 projections for the number of at-risk four-year-olds in each school district and the number of at-risk four-year-olds served in a publicly funded program using available information; - Details the results of the CIRCLE assessment, which was administered to children in publicly-funded four-year-old (4K) and five-year-old (5K) kindergarten during the 2014-15 school year; - Describes the four language and literacy assessments that measure 4K and 5K students' abilities during the 2015-16 school year; and - Discusses how 4K quality can be defined and the important role of teacher-child instructional interactions in assessing quality of publicly-funded 4K. The EOC anticipates preliminary 2015-16 student assessment data will not be available until Spring 2016 and end-of-year data will not be available until Summer 2016. Analysis of 4K and 5K student assessment data for the 2015-16 school year will be addressed in Part II of this evaluation report, which will be finalized later in 2016. (author abstract)