When you pull off some smartass comeback against a crappy teacher that gains everyone else a few glorious moments of banter, but gains you extrawork or a detention.
Teacher: Where's your book?
Smartass: At home.
Teacher: What's it doing there?
Smartass: Having more fun than me.
*insert laughter here*
Teacher: Detention at lunch for not doing your homework.
Skrub: Damn, he just got bookslapped.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.