Because of states' growing roles in education, the study of variation in state educational policies contributes to a better understanding of policy processes and to the prediction of possible policy outcomes. Comparing state educational policies involves choosing variables and analytical designs and defining cases, concepts, and measurement. Variables to study include background and outcome variables, which are already well formulated, and policy variables, which are not. Suggested here as policy variables are policy specificity (how specific a policy's prescriptions are), policy legitimacy (among its constituents), policy effectiveness, policy efficiency (in relation to cost), and policy evaluation (by interested groups). Researchers analyzing educational policies can choose either a "basic" or a "nested" analytical design. The former establishes relationships among variables by measuring the association of variables among the states. The latter first finds relationships among variables within states before analyzing the variation in these relationships from state to state. Interstate educational policy analysis must include definition of cases and ensure the equivalence of cases, concepts, and measures. Single-state case studies, because of their specificity, usually do not generate testable hypotheses for comparing educational policies. (RW)