Ok, everybody is recommending different content sites, so you've got places to go to find specifics. That's good. But you also need a way to figure out what you already know, what you want to know, and which order is best to learn stuff in so you're not confused. For instance, you'd better have a decent understanding of trigonometry, geometry, and pre-calculus before you try tackling calculus. The hardest part about self-learning isn't trying to find tutorials for what you want to learn, it's figuring out how the specific topic you're working on can be contextualized in terms of other topics in the same subject area.
To figure that out, the most helpful thing I've found is looking at example 4-year plans at colleges (and, if they're available, even for some high schools when it comes to the fundamentals of a subject I never took), and, for online any given online course, seeing if there are any recommended prerequisites or co-requisites.
As an afterthought to all that, my favorite tutorial sites are like, HyperPhysics for physics, MIT open courseware for CS topics, HowStuffWorks for general tech-y knowledge (say, if I wanted to learn how a capacitor or a web server worked). If I'm going to google for good tutorials, I usually include something like "tutorial", "introduction", "primer", "layman's guide", or "cheat sheet". I find that even if I'm looking for an in-depth learning experience, the tutorials that are written to be simple will do the best job of emphasizing what's important, and laying out the way that somebody who "knows how to do it" will approach a problem.
To figure that out, the most helpful thing I've found is looking at example 4-year plans at colleges (and, if they're available, even for some high schools when it comes to the fundamentals of a subject I never took), and, for online any given online course, seeing if there are any recommended prerequisites or co-requisites.
As an afterthought to all that, my favorite tutorial sites are like, HyperPhysics for physics, MIT open courseware for CS topics, HowStuffWorks for general tech-y knowledge (say, if I wanted to learn how a capacitor or a web server worked). If I'm going to google for good tutorials, I usually include something like "tutorial", "introduction", "primer", "layman's guide", or "cheat sheet". I find that even if I'm looking for an in-depth learning experience, the tutorials that are written to be simple will do the best job of emphasizing what's important, and laying out the way that somebody who "knows how to do it" will approach a problem.