I was pretty disappointed with my SSAT scores as well. I received a 87% as well. I really needed a 90% minimum. I am a bit distressed about the score. In reality 3% is really only about 4 or 5 questions, but the 87% sticks out like a sore thumb on my application. I got an A+ in Math, Science, Social Studies, English, and Spanish, and an A in music... I feel that Middlesex is a good match for me. My SSAT scores are right on their average, and I have good EC's rec's and all. Now this is the funny thing...
I tested twice
My math increased from a 63 to a 87. Go figure
My verbal decreased from a 90 to an 85
My reading decreased from a 82 to a 78
The test is very much luck of the draw. I don't think that 3-5% lower average can hurt too bad, or can it?