It seems that every student has heard of the advice to fill up as many pages as possible on the SAT essay. Yes, writing more is key to a higher score, but not if it's done by writing with big letters and big spaces.
I was recently asked by a reader of the blog why his essay (pictured below) received a 14 out of 24. I could tell what the problem was just by glancing at the first page.
Look at the spacing between words. With his handwriting, he manages to fit only 6-8 words on each line. The full essay was only 2.5 pages long, and the total word count was 433. To give you a baseline for comparison, the word count in what The College Board considers a perfect 24 essay is 597. That's a difference of 164 words, essentially a full page. He simply didn't write enough and perhaps fooled himself into thinking that he did.
To give you another point of comparison, here is the first page of an essay written by a student who scored a perfect 24:
Notice that she fits at least 8 words on each line. Her full essay was 4 pages long. Yes, her handwriting was messy, but that's what you have to do under time pressure. You have to write fast.
Now I'm not saying you need to write as much as she did, but you do need to aim for at least 3 pages, and putting huge spaces between words doesn't count; it comes off as exactly what it is—an attempt to fill up space. I know you're probably not doing it intentionally—that's just how your handwriting is—but you're still responsible for taking it into account when determining how long your essay should be.
To get a higher score, add more detail, not blank space.