One can certainly homeschool their children without joining a legal defense association, though it might be prudent to at least check into what they have to offer. Home School Legal Defense Association, is one of the largest of its kind. They hold to a conservative Christian worldview, but say that religion is not a criterion for participation in their group. Their website sates, “We work in conjunction with secular and religious groups alike to promote and protect home education freedoms.”
For homeschoolers who are decidedly not homeschooling for religious reasons, or do not agree with the principles that HSLDA adheres to, the <a href="www.homeschoolcoalition.org">Homeschool Coalition</a> may better suit their needs. Other alternatives include hiring your own lawyer if and/or when the need arises and seeking out groups who act as advocates for civil rights cases to intercede on your behalf.
Sources:
www.hslda.org
http://www.homeedmag.com/HEM/185/somilitary.html
http://www.nhen.org/nhen/pov/military/faq_military.asp?id=206#faq2
http://www.homeschoolcoalition.org
http://homeschooling.gomilpitas.com/
http://palmtreepundit.blogspot.com/