There are some really good resources out there for self-study. An easy one to start with is Ron Gross's The Independent Scholar's Handbook, http://www.amazon.com/Independent-Scholars-Handbook-Ronald-G....
But the much older (early seventies) book This Way Out is even more useful. My Amazon review:
This book is in 3 parts, the last 2 Experimental Colleges and Foreign Study are too dated to be useful.
Part one is the best book for college-level self-study I have used. I first read it in the early 1980s and have reread it several times since, it is only 135 pages but packed with useful advice. The biggest weakness for the current user is that it has nothing on computers or the internet, but some of its advice such as "Write lots of short papers. Long papers kill students and tutors alike. Write lots of short papers. It will teach you too write and that, as we will demonstrate later, is essential" could almost have been written for the Web (most books on creating web pages emphasize short, to the point writing). They also mention the absolute essential for self-education - you must love to read, if you don't, then stay in college where they will force you to read.
Also, I would add, for technical fields you need to be interested enough in math to study it on your own as well.
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