Data from state education agencies show that homeschooling has more than doubled, and possibly tripled, in the 5 years between the 1990-1991 school year and the 1995-1996 school year. By the 1995-1996 school year, from 1% to 2% of the total school-aged population were in homeschooling. Homeschooling has become a major sector of the private education world, representing approximately 10% of the privately schooled population. In some states, homeschooling may exceed 20% of the privately schooled population. The total number of homeschoolers in the 1990-1991 school year seemed to have been between 250,000 and 350,000 children nationwide, and around 700,000 to 750,000 in 1995-1996. Based on limited evidence from four states, the number is still growing. The rate was between 7% and 15% from the 1995-1996 school year to the 1996-1997 school year. If one assumes the larger growth rate, which is more consistent with past growth, the number could have reached about 1,000,000 children by the 1997-1998 school year. Growth has persisted over three decades. Earlier estimates, based on different methodologies, suggested 60,000 to 125,000 school-aged children in the fall of 1983, 122,000 to 244,000 for the fall of 1985, between 150,000 to 300,000 for the fall of 1988, and between 250,000 and 350,000 for fall 1990. A retroactive estimate done in 1988 suggested that 10,000 to 15,000 children received their education at home in the later 1970s and early 1980s, close to an estimate made at that time by an early leader of the homeschooling movement, John Holt. One appendix contains a summary of data available from the states on homeschooling, and the other lists families who file homeschooling paperwork by state. (Author/SLD)