This report discusses school enrollment levels and trends in the population aged 3 and older based on data collected in 2006 by the U.S. Census Bureau in the American Community Survey (ACS) and the Current Population Survey (CPS). Historically, the CPS has been the only data source used to produce school enrollment reports. This is the first report to show data from the ACS, supplemented with CPS data where they provide better information. The ACS has a larger sample size and will provide statistics for small levels of geography, which are reasons why it is used as a main source of enrollment data. Highlights of the report are: (1) In 2006, compared with the enrollment distribution of 2000, there were more students in college and high school and fewer in nursery, kindergarten, and elementary school; (2) High school dropouts constituted 11 percent of the population aged 18 to 24 years old; (3) More women than men are enrolled in college, and this has been true since 1979. Women have also become the majority of graduate students; (4) Diversity plays a prominent role among the school population, with differences apparent by geography. In the Western region of the United States, native non-Hispanic Whites were the minority among students enrolled in kindergarten through twelfth grade; and (5) Also in the Western region of the United States, over one-third of students enrolled in kindergarten through twelfth grade spoke a language other than English at home. Comparison of Census Bureau Data Sources on School Enrollment is appended. (Contains 6 figures, 2 tables and 18 footnotes.)