One idea could be that the Head Boy has to deal with a secret society within Hogwarts that is causing chaos. Maybe they are trying to bring back an old dark magic spell. Another could be that the Head Boy discovers a hidden room in Hogwarts that holds the key to an ancient mystery related to the founders of the school. He then has to protect this secret from those who might misuse it.
One plot idea could be Harry dealing with the extra responsibilities of being Head Boy during a time of unrest in Hogwarts, like when there are rumors of a new dark threat. He might have to balance his regular studies, his role as a friend to Ron and Hermione, and his new duties. Another could be Harry using his position to reform some of the old, unfair school rules that have been in place for ages.
One idea could be a head of house having to deal with a new and dangerous dark magic threat within their own house. Maybe the head of Gryffindor discovers that some students have been dabbling in a forbidden spellbook. Another could be a head of house trying to organize an inter - house tournament to boost morale and unity among the students, but facing opposition from other heads of house who think it's too risky. And a third idea might be a head of house uncovering a long - lost secret about their house's founder that changes the way they view their role and the traditions of the house.
One idea could be that the Head Goblin discovers a long - lost magical artifact hidden deep within the vaults of Gringotts. This artifact has the power to change the balance of magic in the wizarding world. Another could be that the Head Goblin forms an unlikely alliance with Harry Potter to protect Gringotts from a dark wizard who wants to steal all the gold and magical items stored there. Or perhaps the Head Goblin has a secret past related to Harry's family, and this connection unfolds throughout the fanfiction.
A plot could be the Head of Gryffindor having to deal with a rivalry between Gryffindor and Slytherin that gets out of hand. They would need to find a way to calm the students down and promote unity among the houses.
One idea could be to explore Harry's life during the summers at the Dursleys in a more in - depth way. Maybe he discovers a hidden magic within the Dursley's house that has been suppressing his true power all along.
One idea could be that James and Lily have to work together to organize a big event at Hogwarts, like an inter - house tournament. During this, they start to see each other in a new light and their relationship begins to develop beyond just being colleagues in their head positions.
Well, one interesting plot could be the Head Boy having to deal with a new dark magic threat within the school that the teachers are unaware of. He has to secretly gather allies among the students to fight it.
A great plot for a Potter Manor fanfiction could involve a mystery that surrounds the manor. For instance, strange noises at night lead Harry to uncover a long - forgotten chamber. It could also be about Harry restoring the manor to its former glory, perhaps with the help of Hermione's research on ancient magic used in the construction of such manors.
Well, a plot could involve the baby boy being a huge Harry Potter fan in a world where magic is real but not as well - known as in the books. The daddy, who doesn't believe in magic at first, is then drawn into the magical world because of his son. They could go on adventures to find hidden magical places, similar to the places Harry and his friends discover in Hogwarts.
A traveler could be from a different magical realm entirely and come to the Harry Potter universe. They bring with them unique magical abilities that both fascinate and frighten the wizards in the Harry Potter world. This could lead to a series of adventures where they either share their knowledge or are hunted down by those who fear the new magic they possess.