@Kdog:
Common Data Set (CDS) | Office of Institutional Research. According to Yale's 2011-2012 Common Data Set, page 9: Yale's 25% percentile ACT = 31, 75% percentile = 35, so OP is within Yale's range.
@mmarilyn11: My advice is to not take the ACT again, as your 31 and 33 are within Yale's range -- and statistically taking the test more than twice rarely increases your score. I would spend the time writing and editing your essays -- as often that is what distinguishes one high performing student from another. Also see:
http://admissions.yale.edu/what-yale-looks-for
"While there is no hard and fast rule, it is safe to say that performance in school is more important than testing. A very strong performance in a demanding college preparatory program may compensate for modest standardized test scores, but it is unlikely that high standardized test scores will persuade the admissions committee to disregard an undistinguished secondary-school record."
