I found this article recently, and thought it was really interesting.
Researchers gave 33 individuals, ranging in age from 12 to 16, an IQ test in 2004. They then gave those same individuals an IQ test again 4 years later, when their ages ranged from 16 to 20. The results they found may change the way we view learning.
The IQ of the participants had changed. Some had increased their scores, and some had lower scores. Some scores changed by almost 20 points! And 20 points is a major change. If the participant had started with a score of 109 and as and ended with a score of 129, they would have changed from average intelligence, according to the Stanford-Binet scale, to a person of very superior intelligence. And that is a big change.
The picture shows the curve of the intelligence scale.
Researchers aren't sure what the differences of the changes are quite yet, but they have some ideas. They believe it might have to do with what we learn, or it could have to do with some people being intellectual "late bloomers."
Whatever the case, this is big news because, before this study, people had thought that IQ remained almost constant throughout life. Now, with the findings of this study, and more research, we may find that this isn't the case. Of course one study isn't going to cause the entire psychological community to toss out the reigning idea that IQ is constant, but hopefully this can open up more research and help to see if we can really improve our IQ's.