The activity:
In a physics class at the beginning of the semester, "one group picked their most important values from a list and wrote about why these mattered to them. The other group – the controls – picked their least important values and wrote about why these might matter to other people."
Results:
"...Among the control group, who wrote about other people’s values, men outperformed women by an average of ten percentage points. But among the students who affirmed their own values, the gender gap largely disappeared."
Source: http://blogs.discovermagazine.com/notrocketscience/2010/11/25/15-minute-...