@Tangie - Yes, but the OP doesn't seem to be interested in the Careers mod specialty schools. What you have described would behave the same way that the regular military lot would, it may even attract those in the military career to work there. There wouldn't really be any point, unless you want to have two military lots in town for other reasons or you want to get rid of the building shell kind, assuming you have one. Are our towns really in danger of being attacked by their enemies all that often or are you gearing up yourself for a military offensive campaign against one of them?

Good idea on the Consort's Dress Code mod, but the sims would only appear to change clothes while on the lot where the sign is. They wouldn't spin into Formal in order to go to school and they would be back in Everyday (or Outerwear) as soon as they left the lot where the school and the signs are. If not using Zerbu's, seems like the effect would be a bit fleeting.