The rhetorical history. Anyways, what % of officers come from the academies?
But, it is not a rhetorical statement, it is quite clear. Now that I make my living as an historian I can safely say there are no well-known military leaders in history who had degrees in education, although there are a good number who were teachers before their respective wars began (Chamberlain and Jackson) and I am sure a tremendous number who later became teachers after their service.
@Pags hit it head on, your degree doesn't really matter.
But...to answer your question (recognizing these numbers are approximate and change from year-to-year) commissioning sources for the Navy are:
Academies - 20%
ROTC w/Scholarship - 17%
ROTC no/Scholarship - 2%
OCS - 23%
Direct Commission - 24%
Other Sources - 14%