This Issue Brief provides estimates of the number and percentage of homeschooled students in the United States in 2007 and compares these estimates to those from 1999 and 2003. From 1999 to 2007, the number of homeschooled students in the United States increased, as did the homeschooling rate. In 2007, parents homeschooled their children for a variety of reasons, but three reasons were noted as most important: (1) to provide religious or moral instruction; (2) concern about the school environment; and (3) dissatisfaction with the academic instruction at other schools. Other reasons for homeschooling included children with physical or mental health problems, additional special needs, interest in a nontraditional approach to education, family time, finances, travel and/or distance. Future reports are planned to use data from the National Household Education Surveys Program (NHES) to study the student, family and household characteristics of homeschoolers and to see how homeschooling rates may have changed between 1999, 2003, and 2007 for different segments of the student population. (Contains 6 endnotes, 2 figures and 1 table.)