The strongest argument for homeschooling is the education that takes place in the public schools, or rather, the lack thereof. Reports on the sorry state of America's schools come out regularly, and it's always interesting to see how many spots we've fallen and what tiny nations (like Luxembourg and the Czech Republic) outscored us academically.
The problem isn't a lack of funding.
Rather, much of it is due to a fondness for egalitarian gestures. As Christopher Lasch observed, "Given the underlying American commitment to the integral high school – the refusal to specialize college preparation and technical training in separate institutions – make-work programs, athletics, extracurricular activities, and the pervasive student emphasis on sociability corrupted not merely the vocational and life-adjustment programs but the college preparatory course as well." People have varying intellectual abilities, and however much it may offend liberals, half the population is below average.