"Not to speak of compulsory biology classes.(compulsory in the sense that girls will not attempt physics)"
They won't?
Look at what they sign up for given a choice between physical science and biology. Stereotype have their basis in fact. The old policy against girls in science was based on the complete disregard of the interests of a small minority of girls in favor of the interests of a larger minority of boys. We have found, of course, that it is easier to put pants on girls than skirts on boys. We can get some girls to take physics easier than to increase the number of boys who will do same, but the grils in the field are still a small number.