Nearly 1 in 5 U.S. students attend rural schools. Researchers report that at least half of public schools are rural in 12 states (i.e., Montana, South Dakota, Vermont, North Dakota, Maine, Alaska, Oklahoma, Nebraska, Wyoming, New Hampshire, Iowa, and Mississippi) (Showalter et al., 2019). Providing quality education to all rural students is a daunting task and needs the support of policy and research. In 2018, the Center for Public Education (CPE) of the National School Boards Association published "Out of the Loop: Rural Schools Are Largely Left out of Research and Policy Discussions, Exacerbating Poverty, Inequity, and Isolation" (ED608842), a comprehensive report on U.S. rural K-12 public education. Today, the data and research presented in the report are about five years old. However, the facts, together with the suggested policies and practices about rural education, are still valid and accurate. After a two-year pandemic, issues related to funding, teacher recruitment and retention, and serving disadvantaged students have become more severe in rural school districts. This five-part series is a data-driven study to inform policymakers, school leaders, educators, and parents. The primary research goal was to examine educational equity for rural students. In Part 1, the report discusses enrollment changes in rural schools and the growing diversity of rural students. Overlooking the broad diversity of rural students can lead to oversimplifying issues in rural schools. To illustrate the diversity of rural students, it not only presents data about the demographic changes of rural students, but also report isolation levels, poverty concentration, regional differences in poverty, and other challenges.