Harry Potter Headcannons

James

I need to talk about James
Of the four boys, James has been the hardest nut to crack. Compared to the other Marauders, even Peter, he is seen so minimally. Which is a shame, because he was such an extraordinary character.
There is this assumption that he was a care-free joker at Hogwarts, that he not only laughed in the face of responsibility, but ignored it all together. Which makes little sense to me. He was the sole heir to a wealthy pureblooded family. Even though they were not as focused on maintaining their better-than-you blood status in wizarding society, unlike the Blacks, James no doubt had to learn how to behave within certain circles.
It's not difficult to imagine the pressure he had to be under, knowing that so much duty and obligation rested on his shoulders. If Sirius was expected to know how to write in perfect cursive, memorize pureblood lineage, and have perfect table manners, you can bet James was too. He may have been raised in a more loving and supportive environment, but the expectation was still there. And considering all that, it makes sense that when he finally gets to Hogwarts and is away from all that expectation and pressure that he lets loose. He goofs off with his friends, pulls outrageous pranks, and has a devil-may-care attitude. Because he finally can.
Even so, don't think for one second though that such behavior bled into his studies. He was essentially a transfiguration prodigy and exceptionally smart. James would have known that it was expected of him to excel in his studies and uphold his family name. He could be outspoken and mischievous, so long as it didn't get in the way of those things.
However, when it came to his friends, to the people he loved, he was willing to put all of that on the line it seems. When he discovered Remus' lycanthropy instead of the expected response (putting as much distance between himself and Remus as possible) he tries to help. And while to many this sounds like merely a kind gesture we have to remember that this was during a time when werewolves experienced extreme prejudice and discrimination. James was likely raised with the common prejudices against werewolves and other supposedly "dark creatures" even if the Potters weren't involved in the Dark Arts like other wizarding families.
Flying in the face of that he researched becoming an Animagi. He would have known full well how dangerous of an undertaking that was, what the consequences of being discovered would entail. But he doesn't let the misconstrued perceptions of others control his response to a friend who needs him. James accepted Remus just as he was, and valued him as a person and as a friend; his condition was merely a facet of who he was. And having found a means to help, he employed all of his wit and ability to achieve his goal.
Which leads me to something which grates my nerves. James' strength of character is underrated much of the time, and in doing so much is overlooked; his becoming an Animagi, his protecting Snape from the very real threat of a werewolf, the bravery it took to turn down Voldemort as a child in school and then defying him several more times during the war (the Longbottoms were Aurors with extensive training whereas James was barely out of his teens). Not to mention the mental faculties needed to help to create the Marauder's Map - which is beyond mind-blowing to consider. Hogwarts is a leviathan of a castle, at seven stories high with additional towers, dungeons, greenhouses, and annexes. To create a map that can encompass something so vast and still be accurate is astounding. To the best of my knowledge there is nothing similar to the Map, which means spells needed to be created to enchant it.
James was intelligent, brave, and above all loyal. Even at his most boorish and crass, during Snape's Worst Memory, he was exceptionally loyal to those he cared about and would rise to the defense of others without a second thought. By sixth year he showed enough maturity and promise to become Head Boy of Gryffindor house, and to the best of my knowledge he excelled in his new duties and responsibilities.
Within a few years after graduation he becomes an incredible wizard, husband, and father. It never ceases to amaze me that he faced Voldemort, the most evil wizard in known history, wandless in an attempt to buy Harry and Lily a minute, even a few seconds, to escape. The amount of courage and selflessness it took to have that be his final act is humbling, and if that was the only thing I had to base his character off of it would be enough.
It's repeatedly purported that James is the stereotypical 'golden boy,' but considering all his accomplishments while attending Hogwarts I think the title might be well earned. Even though James was a pureblood, even though he had nothing to lose personally when it came to aggression against muggleborns, even though he was still incredibly young, he still joined the Order to stand up for others. He recognized that standing up against the violent oppression of others was more important that his trivial problems. Joining the Order wasn't about him loving Lily, it was about doing what was right. It was what defined him, his sense of right and wrong and his unyielding loyalty.