According the CA DOE, for 2005-06, the following SF public elementary schools had the highest proficiency scores (both above 70%) in both Math and Language Arts:
Alice Fong Yu
Robert Louis Stevenson
Claire B. Lilienthal
You can get further information at the link below.
Look for attitude, PTA focus, and the folks who are touring. Clarendon has a pretty "it aint broke so don't fix it" attitude, and if you want to participate, you're sh*t out of luck.