Wait a second. This guy is a Geography teacher, not a Social Studies teacher. Part of the subtext to this entire story is that the teacher was venturing off the study plan by interjecting poitical opinion into a geography class. Not that he'd be in the clear if it was plain, old Social Studies course.
Geography is one course in the social studies curriculum. I often taught it. Current events is a recommended part of social studies instruction. However, the parts I have heard are not prompting a discussion of the speech, but go very far afield into a rant of opinion.
Social Studies include history (world and American), geography, government, economics, sociology and pyschology, or at least that is the list of subjects in Texas.
Social Studies teacher often do current events, but he was way off base and way over the line. You should only spend a few minutes on the current event and then move on to the topic of the day.
I have heard from my seniors that a junior teacher spent most of her time bashing Tom DeLay, so it goes on a lot, I am sure.