Do our examples have to be true or historically accurate?
We’re not allowed to score on correctness of content.

Do you score essays better when they adhere to the standard Introduction (with a Thesis Sentence), Body, Body, Body, Conclusion format?
I don’t give essays any better or worse a score for conforming to the standard “five paragraph essay” format than ones that don’t. That said, those are generally the ones in which students are able to be the most organized in the 30 minutes that they get to write the essay. As long as I know the argument you’re trying to make, I’m not going to dock you for having a thesis paragraph post-introduction. But in a short essay like that, that’s much more difficult to effectively pull off than it would be in, say, a longer research paper.
I do have to say that, from a scorer’s standpoint, the standard five-paragraph format is MUCH easier to score. But it’s also hideously boring, repetitive, and often devoid of creativity. I think it has its place, and the SAT essay is a good place for that. But I’ve seen a lot of essays work that didn’t adhere to that.

In your opinion, what should a top essay have? I’ve heard to put at least 1 pop culture reference and 1 historical reference.
Strong argument, at least three well-thought-out reasons supporting that argument, strong, relevant, specific examples for each reason, and a thorough analysis of the examples in relation to your reasons and core argument will get you to at least a 5. I’ve never really honestly paid much attention to pop culture/historical references, but I will say that if someone only gives examples from their personal life, that to me is a MUCH weaker essay. I want them to look back at all of what they’ve learned and apply that, even if they remember something incorrectly (for example, saying that George Washington freed the slaves.) At least there’s an attempt there to apply knowledge they’ve learned.
The 6th point comes through style–use of language, diction, syntax, vocabulary. Like I said above, a 6 essay is pretty easy to identify–they almost jump off the page at you most of the time. It’s the 3s/4s and 4s/5s that will kill you. Is it a 3 or a 4? Is it a 4 or a 5? Ugh.

Does handwriting affect score?
if an essay had really, really poor handwriting, I’d tend to skim it more quickly than I might otherwise have, and an essay that has been quickly skimmed likely wouldn’t have received as high a score from me as one that was easily legible and allowed me to quickly skip back to and review and ponder the student’s key points and writing style.
Moral of the story: use decent penmanship on those essays, people. It won’t take you THAT much longer. Outline on another page first if you must. Having taken a number of AP tests and SAT subject tests when I was in high school, I remember the pressure of timed tests. But the more easily the scorer can read your writing, the better they will be able to evaluate it.

Handwriting doesn’t affect the score unless we can’t read it. We can’t score what we can’t read.

Is creativity valued?
No. Formulaic essays, unfortunately, are much better. Creativity unfortunately won’t generally get you very far.

Can we make up examples?
Examples ARE allowed to be made up–this IMO is one of the lesser-known secrets. As long as they’re STRONG examples, and don’t tell us they’re made up, and you’re convincing with your BS, GO FOR IT.

Should I use big words? Will they improve my score?
Not specifically, but a stronger vocabulary is one major thing that separates a 6 from a 5. As long as the words are use correctly and appropriately, though. Randomly throwing in ANTIDISESTABLISHMENTARIANISM isn’t going to win you any points.
Vocabulary used appropriately is generally the cherry on top that bumps an essay from a 5 to a 6. It can also bump a score up from one level to the next with scores other than 5/6, but overall, yeah, we go for a concise, cogent, convincing argument first.

Do you take off points (and if so how much) if an essay is not complete? There is not much time given to you when writing the SATs essays, so I would imagine there are a lot of people who do not finish their essay.
Nope. I’ve given essays a 6 that didn’t have a conclusion. It depends, again, on quality of argument and if you were able to say what you needed to say.
I’ve also given 5s and a rare 6 to someone who outlined their final paragraph–it was clear that they were running out of time, but had a strong argument to make. Writing the full paragraph is better than outlining, but outlining is better than not writing anything at all.
I’ve given 5s (and the rare 6) to essays without a conclusion, esp. when the person made a great argument but ran out of space/time.
That said, a conclusion is the whipped cream sometimes–not essential, but can really tie a sundae together.

Do you prefer a passive or active voice?
Active

Do Longer essays get better scores?
not necessarily. Longer essays generally do score better just because they have more room to make an argument, but that’s by no means a hard and fast rule.

What makes an essay a 6 (perfect score from one grader)?
For a 6/6 essay, I looked at:
quality of argument
strength and relevance of reasons to the original argument
quality and strength of examples
quality and strength of analysis
vocabulary/grammar/overall writing style

What are sat essay grades based on?
The collegeboard official scoring rubric: http://professionals.collegeboard.com/testing/sat-reasoning/scores/essay/guide
Should we argue one position or both?
I get frustrated with students when they sound wishy-washy, mostly because they’re too lazy/scared to have an opinion on something. BE DEFINITIVE!!!
When it comes to standardized test essays, even if you don’t believe what you’re arguing, argue it anyway, as long as it’s a strong argument. For example, say you believe the death penalty is wrong, but you can come up with a stronger argument as to why it’s right–ARGUE THAT!! The essay scorer is never going to meet you or know who you are.