If I were a school teacher, there is something I would like to teach regardless of what subject we were learning: Not everything I teach you is true.
No matter how good your teacher is, or how logical the readings and lectures, nothing is 100 percent accurate.
Some of the facts passed down from generation to generation may be flawed, or may even be invented by a researcher who wanted some admiration back in 1717 or 2010.
Don't assume the writer or teacher is always correct. They are humans, after all. There may be other ways to look at facts - different perspectives, different interpretations.
If you don't understand something, don't assume you are not smart. Some articles are written by reporters who don't understand the subject they are writing about; that may be why you don't understand the article. The article doesn't make sense to ANYBODY.
Just because there is a new discovery or understanding does not mean it is superior to the old.
Some teachers do not tolerate debate very well; they sincerely pass down what they have been taught, most of which is likely very useful, and do not expect to be challenged. The student doesn't have to question the teacher. Just keep an open mind about what you learn.