“If it takes color-coding or ponies and hairdressers to get girls playing with Lego, I’ll put up with it, at least for now, because it’s just so good for little girls’ brains,” says Lise Eliot. A neuroscientist at the Rosalind Franklin University of Medicine and Science in Chicago, Eliot is the author of Pink Brain Blue Brain, a 2009 survey of hundreds of scientific papers on gender differences in children