The plot could revolve around the seven forming a secret club in high school. They could be using the club as a cover to train for their demigod duties. They might face challenges from new monsters that are disguised as high school students or teachers, and they have to figure out who is a threat without blowing their cover.
Perhaps the fanfiction could focus on the relationships among the seven in a high school setting. Annabeth could be helping Percy with his studies, while Piper and Jason are dealing with the drama of high school romances. Leo might be using his mechanical skills to create cool gadgets for the group in the school's workshop, and they all have to come together to face a powerful enemy that targets their high school.
Percy could be the most popular. He has that charm and his water powers are really cool. He'd probably be a star on the swim team, which would earn him a lot of admirers.
Well, maybe Percy could be poisoned by a monster in disguise at school. He starts feeling really sick, like having a high fever and being super weak. His friends, like Annabeth, suspect something is wrong and start investigating. They might find out that there's a new threat in the school that's targeting demigods.
He might face a lot of challenges. For example, without his friends, he would have to deal with the monsters on his own. Maybe he'd struggle in classes because he's used to being on quests rather than studying. Also, he could become a loner and be misunderstood by his classmates.
One possibility is that Percy could be a new student at the high school where Artemis also attends. There might be some initial misunderstandings between them due to their different natures. Percy, being a son of Poseidon, is used to a more free - spirited and sometimes reckless approach, while Artemis is very much in control and values her independence. Their first encounter could be quite tense, like when Percy accidentally interrupts one of Artemis' important meetings at school. However, as time goes on, they could start to respect each other's strengths and form an unlikely alliance to face some common threats within the high school, like a group of bullies who are actually minions of some minor god causing trouble.
In a fanfiction about Percy Jackson's high school reunion, there could be a lot of drama. For instance, some of his old classmates might be jealous of his adventures. Percy could meet a girl he used to like, and she could be dating someone who doesn't believe Percy's stories. So Percy has to prove himself by using some of his demigod powers in a non - threatening way. Also, his old friends from the demigod world might bring some mythical creatures as a surprise, causing chaos and excitement.
Well, one possibility is that they face challenges related to hiding their demigod identities while trying to fit in at a normal high school. Maybe Percy has trouble in a swimming class because his powers make him too good and he has to hold back. Annabeth could be acing all her academic classes but struggle with the social drama that comes with high school.
One possible plot could be Percy dealing with PTSD from Tartarus while trying to fit into high school life. He might have nightmares that disrupt his school days and struggle to make friends who can understand his past traumas.
It could be a new demigod who has turned to the dark side. Jealous of Percy's popularity and Artemis' power, this demigod could try to create chaos in the high school and turn students against them.
The school principal could also be an interesting antagonist. Imagine if he or she has somehow been influenced by a dark power from the mythological world. They start implementing strict and unfair rules at the school that target the demigods specifically, and Percy has to figure out a way to break the influence without getting expelled.
A teacher at the high school could secretly be a minion of an evil god. They could be trying to undermine Percy and his friends by giving them unfair grades, getting them in trouble with the principal, and generally making their high school life miserable. This would be an interesting take as it's an unexpected source of conflict.