So I have less time to put these together, but I remembered there was a better game for group storytelling, that would take less effort to organise and that we can all contribute to.
It's called Finish the Story. The basic way to play it is:
One person starts a story, contributing just one sentence.
Then the next person continues the story in the same fashion, until everyone has had a turn.
There can be as many rounds as the group wants, but for the sake of keeping each chapter short and sweet we'll have two rounds, meaning two turns for everyone. So if you have just had your turn, since we don't know how many people are playing and when, maybe wait for 2 or 3 people to have their turn until taking your next one.
The objective is to have fun of course and tell a great story. So add on to what the last person has contributed and make sure that it's in line with what has occurred. So not changing anything that has been established and in this case because it's based on ST and the setting is September 9th to 14th, 1985, don't add anything that wouldn't have occurred at that time (like a demogorgon suddenly appearing or Hopper, unless it's a flashback and stated as such) or material from other media not from the show.
In this version of the game I'll set the scene, but it's not the start of the game, so it will be more than one sentence. Then the first person to comment officially starts the story. The chapter takes place during the day given in the intro and so the events do not proceed any further then that day. Here we go:
Monday, September 9th. 1985.
Eleven is sitting inside the staff room of Melvald's General Store. She is doing her homeschooling there while Joyce works out front. They each have walkie talkies so El can ask Joyce questions related to her studies. At the moment, El is reading Anne of Green Gables for English. It's lunchtime, so Joyce closes the store to take her break and joins El in the staff room.