Gender gap discovered in the 1970s has been closed, researchers say
                                
                                
                                    (Newser) -
                                    Girls are just as good as boys at math, says an exhaustive study of 7 million test scores from elementary through high school students, the San Jose Mercury News reports. The findings, to be published tomorrow in Science, are at odds with 30-year-old studies—and a view entrenched in our...