For some reason I can't post in the "Math & Science Learning Materials" section, so I'm posting my inquiry on the quality of the learning materials I'm using here. I'm aware there's a lot of free resources such as KhanAcademy or otherwise, but how legitimate is the information compared to say, OpenCourseWare lessons from MIT in a subject such as physics? Is there a "right" or "better" way to learn something? I'm asking because when I was learning how to program, I was taught that the "correct" way was not to just read a book and learn a language's syntaxes, but was first introduced to a textbook titled SICP (Structure and Interpretation of Computer Programs) which first taught me how to actually program, and then moved on to learning how to write code using a language (though SICP used a dialect of Lisp called Scheme as its example languages throughout the text in order to teach logical programming). I was told that should I have taken another path such as learning something like Python or object-oriented C++ as my first language without learning how to program functionally first, that I would've developed bad programming habits which would take years of effort to undo and re-learn how to program "properly." So I am wondering if the case is similar with math/physics or any other science in general. Is there a correct way to approach such subjects, or can one just dig in and soak up anything they can in no particular order? I obviously don't want to learn incorrect knowledge either, but I'm sure if any reputable information source had mistaken facts, then they would promptly fix/edit/remove it, so I still trust websites like KhanAcademy. I'm just cautious about going into those fields and optimizing my learning methods.