My friend (>:|) started talking to me about someone writing a Steddie JP AU, but all that did was make me really want a Camp Cretaceous AU with the Party. So please come along with me for a moment.
Will Byers wins an art contest to get there. Dustin beats a video game. Mike enters a storytelling competition. Max's skateboarding sponsors send her. Lucas and Erica's mom is one of the lead scientists, so they usually live up the island with their dad, who lets them go to the camp to hang out (which incidentally means neither of them but especially not Erica is impressed with the camp). El... no one's quite sure how El got there. She's quiet.
The camp counselors, Steve and Eddie, introduce themselves at the dock and take the new arrivals to the camp to meet Lucas and Erica. Everyone hits it off well that first night, trading their stories about how they got here, talking about dinosaurs. Most of them actually do like dinosaurs, but there's a line drawn in the sand about whether these even ARE dinosaurs (Will and Dustin argue they are NOT, Lucas and Mike argue that they ARE, Max doesn't care she just thinks they're cool, Erica doesn't care she just thinks they're not cool, El doesn't really know what dinosaurs are, but it's her fault they got into the debate).
They actually get to spend a few days on the island before shit hits the fan. Getting into shenanigans, learning the layout, seeing things that will come back later. Getting little hints of the evil going on behind the scenes, but in ways that don't particularly set off alarm bells until you're looking back.
And then the indorex breaks containment and the island gets abandoned. The kids are out when it happens, maybe in the riding balls so they end up relatively safe, but not recovered. Steve and Eddie stay behind to try to find them, but they JUST miss each other several times, and finally they're forced to leave the kids there despite KNOWING in their BONES that the kids ARE alive.
The kids spend the next 6 months surviving the wilds of jurassic world. Dustin befriends a dinosaur he names Dart and gets lost in the woods for a while when they get separated. They build a fort from the remains of the camp. They go on adventures to acquire food and drink and try to communicate with the mainland. They face off against opportunistic poachers and nearly escape on the boat, eventually making it to the nearby island and finding out all the lurking evil from the first half of the story has come back to bite them, and they can't go home without saving the dinosaurs from the Russians running some kind of underground dinosaur fight club.
Meanwhile on the mainland, Jonathan is mourning his little brother while Joyce is trying to figure out how to get them to the island to go looking for Will. Nancy turns up because she caught a wisp of communication from Mike from one of their attempts to contact home, and she KNOWS they are alive. So the three of them start digging and end up in contact with Steve and Eddie who are like yeah we got you, we can get you there, we know the place, we'll come help. So THEIR group ends up heading to the islands to look.
Hopper, meanwhile, as head of security for the island, has been losing his mind because he cannot think how this happened except one of his team failed but he personally vetted the whole team, they were all exceptional. it HAD to be sabotage. Someone was not telling him something. He's furious. He ends up going to the island to investigate , and runs aground of Joyce's group, and ends up joining them.
They find evidence of the kids on the island, and then somehow end up in radio contact with the kids on the other island. They call in authorities (hello Sam Owens), and hop islands to go get the kids, who by this point have definitely befriended Murray the scientist who is 99% certain there's a conspiracy going on he hasn't figured out yet and Dmitri, one of the robots they've reprogrammed to be on their side instead. They're getting ready to go head to head with Dr. Brenner, El's "dad" in some way, when Joyce's group finally gets to them, and it's getting kind of grim until Sam's group also arrives, and everyone gets rescued and/or arrested and the place gets closed down and our people all get to go home.