Here is an excerpt from the screenplay for the movie of my job.

Me: (explains complete assignment)
Mike:  "How do you say 'to'?"
Me: "'A.'  Henry, get rid of that ice cream, you know you are not supposed to eat in here."
Albert (to friend): "Whatever the cowboys suck!"
Me: "Albert, stop talking about irrelevant things and do your work."
Albert (slightly lower): "The coach doesn't matter, they just suck."
Me: "Albert, shut it!  You haven't finished your stuff and are about to get a bad grade."
Mike: "How do you say 'to'?"
Me: "A."
Me (in hallway for brief respite) to student listening to ipod and talking on cellphone, ambling through hallways during classtime: "Do you have a pass?"
Student: "I aint got no pass I'm goin' to meet ma friend."
Me: "You cant be in the hallway without a pass, you need to leave."
Student (acting like he's talking to someone else although at this point his phone is closed): "MAN I AINT TRYIN TO HEAR WHAT THIS CHICK SAYIN"
He leaves, I return to class.
Mike: "Um, Ms. Miz??  How do you say 'I go'?" (I taught this concept roughly 3 months ago, with practice almost every day).
Me: "Voy.  Do you have your notes?  It should be in there."
Mike: "I guess I lost them.  Um, how do you say 'to'?  Like, 'I go to...'?
Me:  "A.  So, 'voy a'.  Maybe you should write that down, you keep asking the same question."
Random student: "Cowboys gon' win."
Albert: "No they NOT! They suck."
Me: "Albert!  Shut your mouth!"
Albert (sheepishly): "Sorry miss."
Albert (he has been sitting next to Mike, but not heard any exchange because of his excessive talking, and is now finally starting his work): "How do you say 'to'?"

Bell rings.  Pausing to regain sanity, I glance at the floor as students trample out.  The revolting remains of Henry's ice cream and wrapper fester under his chair. I grade Mike's paper and realize that he has mastered the "a" concept 3 times, and every other time he has used the English word "to."

For the actual movie, this script will have to be  scaled to reflect equally infuriating conversations with over 200 students.