State content standards are the backbone of the standards-based reform movement. Content standards provide teachers with a set of guidelines for what students are expected to know and be able to do, defining the intended curriculum. And although the current 50-state system of education gives each state the task of setting content standards, there has been little empirical investigation of the similarities and differences among state content standards. This analysis uses the content analysis procedures of the Council of Chief State School Officers/State Collaboratives on Assessment and State Standards to consider whether there exists a de facto national curriculum as defined in state content standards. Data from English/language arts and reading (ELAR), science, and mathematics for Grades 4, 8, and K-8 are used. Results suggest considerable variability among states in the content of content standards, particularly in individual grades, but also for the aggregated standards. Further analysis suggests that state standards are no more well aligned to national professional standards (i.e., National Science Education, National Council of Teachers of Mathematics) than to other states' standards. Still, there exists a small "core curriculum" across states in each content area. The level of focus of the state standards varies substantially across states, and the redundancy of the standards is such that alignment within state, across grades is often as high as alignment within grade, across states. Policy implications are briefly discussed. (Contains 6 tables and 7 figures.)