... consider what happens when students are told "Do what you are good at!" Loosely speaking the situation will be something like this: females will say I got As in history and English and B’s in Science and Math, therefore, I should follow my strengthens and specialize in ... history and English. Boys will say I got B’s in Science and Math and C’s in history and English, therefore, I should follow my strengths and do ... Science and Math.This explanation can be understood in terms of marginal analysis of two tasks, i.e., the opportunity cost of doing one is the foregone benefit of doing the other. For boys,
which drives their revealed preference for math (or STEM) over English (non STEM).