Probably remove that part if the passage really adds nothing to the story, whether in terms of the information conveyed or how other characters react to it, but don't just delete it- paste it into a scraps file, and make sure the information is safely logged in your worldbuilding notes. You might know now where the story's going to go, but you never know if some tidbit of that passage might come in handy later for something little, like an offhand joke or remark, or inspire something else entirely, like an addition to your story that you wind up liking better, or even an entirely new story.
"Jack, you have debauched my sloth."Hmm... I might say that, if it's kept very short indeed, it might be okay to keep it: such things can help to make a world feel like it extends beyond the immediate story, I feel.
That said, if it's longer than "very short indeed", then it does run the risk of bringing the narrative to a grinding halt for little purpose. Thus keeping it is a risk, and one perhaps to float past some readers, if you decide that you want to do so.
(There is also the option to veer fully into Narrative Filigree—but be careful in doing so, as it's a dangerous path, and I recommend that you only take it if you specifically want the sort of result to which it leads.)
Edited by ArsThaumaturgis on Apr 30th 2020 at 3:05:07 PM
My Games and Asset PacksI think you could also fairly easily transform it into something functional. E.g. establishing that the teacher is not very interesting, or the teacher being interesting but the character being uninterested. A bit, essentially, about how the characters deal with it while still delivering exposition. Harry Potter often paints history classes as boring, but making it important for context later.
Another option is to simply explain certain dynamics to the reader. In The Expanse, there are occasional history lessons to emphasize that while this is futuristic sci fi in space, it is not free from the clutches of history and things that happened hundreds or thousands of years ago will still resonate. That physically, humans have not changed that much since our hunter-gatherer days.
Edited by devak on May 1st 2020 at 10:01:12 AM

There's a scene in my story where the protagonist is listening to a history lecture. During this lecture, the teacher goes on a tangent about local history and how the fictional city was affected by national events. Beyond fleshing out the history of my fictional city, it serves no other narrative purpose. This information doesn't come back to influence the story in anyway. Given this, should I cut this tangent or is world building a good enough justification to keep it?