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An organization that develops homeschooling curriculum, many times manifesting itself into a certain family lifestyle (see Gothardite).

Usually refered to as ATI (or ATIA, for old-timers), it has a connotation of strict rules, large families, and the infamous navy & white clothing.
"Did ya see that new family? There must be like a dozen kids and they were all wearing navy & white....I think they're ATI for sure."
by jay February 21, 2005
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