Contact lenses, that is!
About a month ago, I suddenly noticed I couldn't read stuff that was far away anymore. I let it go though, thinking I was just tired and/or stressed. When it didn't stop, I made an appointment at the local eye doctor, which I had today.
Turns out that my vision had went from 20/20 to 20/50 in one eye and 20/60 in the other! It seemed like it happened over the course of a day or so, and the doctor said that it's not unlikely that it did. He said it's very common for juveniles to have a loss of vision in the short period of 48 to 72 hours, due to a growth spurt!
Turns out I'm near-sighted. Here's something interesting he told me; people that are near-sighted tend to have an over-developed cerebral cortex, though they're not sure why. Apparently near sighted people tend to be more intelligent than people with normal vision or people who are far sighted.
Another interesting statistic is that the majority of people in prison are far sighted!
Here's something else that everyone should know; the doctor said that you really shouldn't wear those color contact lenses for sight, they're really dangerous. The clear part of the lense in which your pupil is supposed to show is only 5mm big -- to give you an idea, my pupil was 5mm big when he was shining a light at it! He said if I were to wear those at night, where my pupil would enlarge, that my vision would become hazy, and I'd start seeing glares in lights. He said they should be taken off the market.
Hope all of this teaches you something!