Yes, of course! www.lesswrong.com/concepts
There are tags for each of those and many more. Scholarship & Learning, Life Extension, Effective Altruism, Happiness.
I think tagging is pretty inconsistent. Any index would probably not be maintained. I'd recommend the search feature.
Random idea: Once in a while we could do something like "LessWrong Wiki Improvement Thread". Choose a topic that is important, and start a discussion about how the wiki page on that topic could be improved. People can use search and submit relevant links in comments; or propose different ways of how the page could be organized. Later someone can implement the best suggestions and add links (the thread author could precommit to do that in a week).
Alternative title for the threads: "LessWrong Wiki Article of the Week / Month: ".
Sounds like a great plan, except that historically
Later someone can implement the best suggestions and add links (the thread author could precommit to do that in a week).
has essentially never happened.
I think that this is a great idea. Less Wrong needs to work on more collaborative projects, but there isn't enough organisation to do anything massive. These projects are about the right size.
I don't know of any index. However, Top scoring posts is good, as are user pages. Luke has collated research posts before. Beyond that, as you mention, the sequences are good.
On the home-page under rationality materials.
And you should have asked this question e.g. in the open thread.
By the way did you introduce yourself in the welcome thread?
And you should have asked this question e.g. in the open thread.
I don't see any reason why this thread shouldn't stand on it's own.
There is the References & Resources for LessWrong (last updated in 2011), which has a good selection of older posts and other resources by subject.
Pardon me, please, if this is not the way to go about asking such questions (it's all I know). Is this more for LessWrong itself, or for LessWrong Discussion?
Is there some kind of comprehensive organization by subject of LessWrong posts?
I know there are the sequences, but also a lot of other useful posts.
If I want to learn about learning, about lifespan extension, about charity work, about happiness, etc., is there a place I can go to view all relevant posts in each respective area?
Thanks much