Girls and STEM

According to Education Week, girls are being outperformed by boys in science and tech classes including Biology, Chemistry and Physics.  This gap gets bigger as kids age.  I would have thought that the opposite would be true.  What are we doing to our girls?  Are we purposely scaring them away from STEM related career choices?  And don't even get me started an what we are doing to our African American girls when it comes to STEM.  We need to show our girls that they do belong in the science and tech fields.  My question is, how are you exposing girls to and promoting STEM in your classroom?