What grade are you in? You'll hear this 1,000,000,000 times, but 700+ is really the place to be for SAT scores.
That said, I believe wholeheartedly that test scores can be improved. Tutors, test prep courses, and even taking practice tests and writing on your own can make a huge difference in your scores. I was able to improve one section by 80 points in a month, simply by practicing testing under the time limit.
But I'm not a fan of patronizing people with comments like, "Anyone can do it. The SAT is not a difficult test." Neither is true.
I had a 710 in math, and 580 in critical reading and I got in...of course there is much more beyond that that got me in too. You have to think about the whole person score.