Impulsive

I have never (Never!) and so many impulsive students as I seem to this year. And all in one class (perhaps the behavior becomes exaggerated in students because of being in a class with others like this?)!
How do I describe it? It's constant noises, blurts, blahs, humms, eeks. Random words, bits of songs, a short thought.
Today I introduced a short movie clip about the Pythagorean theorem. I talked about the song, the movie, the actors, etc. All over, the constant buzzing this class always has. I pushed on:
Me: "So, this clip is from an older movie..."
Student: "Leave it to Beaver!"
Student: "Beaver?"
Student: "I like TV!"
Me: "No, an old movie, in fact it has an actor that was also in the film White Christmas"
Student: "Snow!"
Student: "For white people?"
Student: "I love that movie!"
Me: "Okay, let's just start"


The strange part- it really seems to just be an inability to filter from their brains to their mouths. I've had the mean kids that want to run the class, I've had the kids that just want to goof off... but that's not it this year. This is one of the nicest groups, this group is always enthusiastic about learning and ready for just about anything I throw at them. They just don't stop making noise. EVER. EVER. So, I keep it to a dull rumble or buzz about the room and I move on. But GOODNESS, it can wear a gal out.