# data[].attributes.body
Usually when a student is happy (silly) it's signaled by the curve of the lips into a smile or there's a gleam in the eyes. On the more spirited student, it becomes a combination.

# data[].attributes.body
It's a terrible picture, but I usually look for the student who is looking to everyone else. They usually aren't understanding the concept and they're looking to others to see whether their peers understand it. It's usually them seeking affirmation that they aren't the only ones lost.

# data[].attributes.body
Most times with students, the key indicator for sadness is the post-crying eye. Red, puffy around the socket, it's the tell-tale sign. Teens often try to hid emotional distress; definitely look for these.

# data[].attributes.body
That glazed over eye usually communicates that the listener has stopped paying attention. The eye may follow you, but there isn't anything behind it. It's a good signal for teachers to spice up the lesson and change the pacing.

# data[].attributes.body
From my experience, before the eruption, there comes a flaring of the nostrils. In the calm before the storm, this is the signal that outbursts and gnashing of teeth is imminent.