Call it a blessing. You will, of course, need to navigate his personality to fish out a grade, but an important lesson has already registered with you, and you can take it farther: In life, sometimes, you outpace your teachers.
You will have to decide whether this teacher is shallow enough to grade based on agreement to his isolated doctrine, or if he has the wisdom to credit thought that differs from his own. Choose wisely, and know this: your elders will almost invariably carry more wisdom than you think.
Government classes, for all that they purport to be simple expositions of fact, are in truth one of the most subjective areas in education. A creative writing class has a more unified central ideal! You will be forced to regurgitate things that you do not believe, whether this man is a wizard or a sycophant. You will be disabused of all you learn in that class as you try to reconcile it to life. It is best understood as a sort of Mythology class, in a sense. This will become more apparent, the older you get.
But you have a head start. You know he's out of touch, in a predictable way. You can lead him around by pandering to his spin on things, or predict what will raise his hackles and tiptoe around them. And most importantly, you can see that this area of knowledge is important and that your teacher is not up to the task of showing it to you so---
-- Teach Yourself. You know, after you juice him for a high grade. You have your whole life to read.
If I read the signs here correctly, it may not be your own grade you are concerned about. The question of helping others is more complex. Tell them like I told you; truth is not the object of the game you are in. He is likely to be harder on boys than on girls, given his spin.
Go girl. You show some pluck making such an assertion about your teacher. This could be a major skill as you carry forward in life. Show humility at all times, but poke the Tiger of your disbelief at every turn within that cage.