These research results on homeschooling. Sources are Kunzman and Gaither’s “Homeschooling: A Comprehensive Survey of the Research” (2013, Other Education: The Journal of Educational Alternatives) and others listed below.
First, homeschooling has opposite effects on verbal versus math scores:
Given this persistent corroboration across two decades we might conclude, tentatively, that there may be at least a modest homeschooling effect on academic achievement–namely that it tends to improve students’ verbal and weaken their math capacities. Why? Answers here are only speculative, but it could be that the conversational learning style common to homeschooling and the widely-observed phenomenon that homeschoolers often spend significant time reading and being read to contribute to their impressive verbal scores, while math is not given the same priority (Frost & Morris, 1988; Kunzman, 2009a; Thomas & Pattison, 2008).
Second, as usual, what parents do is overrated:
[H]omeschooling does not have much of an effect at all on student achievement once family background variables are controlled for. This conclusion is implicit even in many of the HSLDA-funded studies, which consistently find no relationship between academic achievement and the number of years a child has been homeschooled (Ray & Wartes, 1991; Ray, 2010).
Third, as usual, who parents are is underrated:
[P]arental background matters very much in homeschooler achievement. Belfield (2005) found greater variance in SAT scores by family background among homeschoolers than among institutionally-schooled students. Boulter’s (1999) longitudinal sample of 110 students whose parents averaged only 13 years of education found a consistent pattern of gradual decline in achievement scores the longer a child remained homeschooled, a result she attributed to the relatively low levels of parent education in her sample. Medlin’s (1994) study of 36 homeschoolers found a significant relationship between mother’s educational level and child’s achievement score. Kunzman’s (2009a) qualitative study of several Christian homeschooling families found dramatic differences in instructional quality correlated with parent educational background.
IX. Transition to College/Adulthood
[M]ost of this literature is quantitative, consisting for the most part of surveys of admissions officers. The consistent finding of such studies is that homeschooled applicants are accepted at roughly the same rates as their conventionally schooled peers, that admissions staff generally expect homeschoolers to do as well as or better than their conventionally schooled peers in college, and that while colleges and universities welcome homeschooled applicants, most do not go out of their way to provide special services or admissions procedures for homeschoolers (Duggan, 2010; Haan & Cruickshank, 2006; Jones & Gloeckner, 2004b; Sorey & Duggan, 2008). One qualitative look at attitudes of admissions officers at three institutions, however, found that many officers privately believe that homeschoolers are close-minded religious bigots, suggesting that what such individuals report on surveys might not always tell the whole story (Millman & Millman, 2008).
Via Bryan Kaplan