text: Before taking a further look at whether such an ability is needed in classrooms, it is imperative to first understand just how the Facial Action Coding System works. It starts by analyzing the face and constructing a 3-D model of it, so that the 44 major muscles in the face can be easily captured. Then, the system labels slight muscle movements -known as action units- in the face and uses those to calculate emotions. As of right now, there are six classified emotions to compare the facial muscle movements to: Happiness, surprise, anger, disgust, fear, and sadness.