Let the aspiring actuary answer this.
Given that the chance of a randomly selected AP Micro Econ student getting a perfect score is 33/67782, the chance that 11 of 15 randomly selected AP Micro Econ students got a perfect score is
15! / (11! * 4!) * (33/67782) * (32/67781) * ... * (22/67771) * (67785/67770) * (67784/67769) * (67783/67768) * (67782/67767)
-- which I don't want to calculate, but I assure you it's low --
and this is if we assume independence.
The logical conclusion is Target is not the only outfit to get hacked recently. The odds, I think, are somewhat less than finding a Higgs Boson.