Added this gem of hidden lore:
The Frigates of EVE also mentions that there is mandatory 2-year period of mandatory service with an enlistment age of 14, implying that all Minmatar youth are trained in some way or another for the defence of the tribes. The enlistment age for actual Republic forces is given as 17. As speculation, this probably means that the common mandatory schooling is for clan militias / local forces, and possibly as mandatory classes / cources / camps during other training rather than full-time service.
Boom, you have military training. Possibly shoddy and cursory such, but still.