How the hell do you have a conversation?

So far I have:

"Hows it going?"
maybe drag out their response a couple seconds

"How was your weekend?"
drag that out for like a minute

"What class you have next?"

"Did you do the assignment for X class"

then its just awkward pause

I usually silently ignore people I don't want to talk to.  It's harder irl, but you can quickly get used to it.  Just don't open your fucking mouth to spew out some meaningless bullshit you don't want to say anyway.