/sci/ - Science & Math

>>8814490

>>8790453

>>8437299

>>8436925

>>8390353
>professor provides the last 4 year's exams, 40 problems a week all worked out on video with commentary, practice quizzes, and wrote his own textbook to save you money

How do we learn things and keep it with us? I recently went on Khan Academy, and the things that were so simple to me in junior high are half remembered now, and completely foreign to me. The math concepts that were so simple that I thought were engraved into my brain are now lost, and won't be retrieved without a lot of effort and relearning on my part. How do you keep what you learn? I can read a few books on astronomy, but 5 years from now I might have forgotten 90% of what I learned from those books. Along a similar vein, watching a nature documentary or a similar program of 'educating entertainment' gives me this good feeling. This feeling of 'getting smarter', I'm learning facts that I never knew before that interest me. But I can not tell you a single god damn thing from Planet Earth, despite watching the whole thing at least a couple times. Is it the mindset while learning the information that is important? Certainly while watching a documentary I'm relaxed, and while studying a subject I'm focusing more intently. But as I said before with my high school math knowledge, even things that I've studied for months and even years have faded away. Is the only way to truly keep knowledge is by constant, never-ending use of it? Then how does anyone become truly knowledgeable about anything without working in the relevant field of that knowledge?