At the beginning of the school year, the Headmaster appoints new prefects, as well as one Head Boy and one Head Girl from all of the seventh year students. These students are chosen because of their academic achievement, outstanding reputation as a student, and an honest, good, and hard-working personality.
Lily became Head Girl in her seventh year at Hogwarts. Although between Lily and James, Lily was by far the more responsible of the two. It took her a while before she eventually came around to the idea of being with James. It wasn't until he stopped being so arrogant that Lily began to date him.
There is one Head Girl and one Head Boy to represent the whole of the Hogwarts Student body. They can be in different houses or even the same. They tend to be, but don't have to be, previously Prefects.
It is possible that Hermione would have been made Head Girl had she returned to Hogwarts for her seventh year, and if Hogwarts had remained a place that she could go to. However, she chooses instead to accompany Harry to help him deal with Lord Voldemort.
Draco Malfoy
If there was any prefect who abused his power for no other reason than to lord it over the other characters, it was Draco.
He was in need of recognition and Dumbledore saw that. Conversely, Harry had more than enough recognition, and making him a prefect would've just been one more reason for people to have an opinion on him and his behavior. Dumbledore knew Harry didn't need more speculation or attention than he already had.
These five students share the same dormitory, and the books have made it quite clear that there are no other Gryffindor boys in that year with Harry. Edit 1: And there were three girls— Hermione Granger, Parvati Patil, and Lavender Brown.
Here is a list of Slytherin females: Pansy Parkinson. Daphne Greengrass. Astoria Greengrass.
Appointment. At the beginning of the school year, the Headmaster appoints new prefects, as well as one Head Boy and one Head Girl from all of the seventh year students. These students are chosen because of their academic achievement, outstanding reputation as a student, and an honest, good, and hard-working personality ...
In the original books, boys are prohibited from entering the girls' dorms. There is a scene where Harry and Ron attempt to go and meet Hermione in her dorm, but as they are about halfway up the staircase, it suddenly becomes flat, and they are sent sliding back down.
Anyway, to answer your question: in the movies, girls can wear either pants or skirts; IIRC, Ginny wears pants, at least sometimes. (Presumably, there'd be no rule against the reverse, but we never do see a male student in a skirt or kilt in the films, at least not that I've noticed.)
A Prefect at Hogwarts was a student who enjoyed a level of seniority over the other students, complete with a Prefect badge. One male and one female student in their fifth year from each house would be chosen for the role of Prefect, such as Ron and Hermione for Gryffindor in Harry's fifth year.
Hogwarts School of Witchcraft and Wizardry was founded by four of the most brilliant witches and wizards of their time. It was founded in the 10th century by Godric Gryffindor, Rowena Ravenclaw, Helga Hufflepuff and Salazar Slytherin.
Eventually, McGonagall became the Head of the Transfiguration Department as well as the Head of Gryffindor House.
Charity Burbage floats helplessly above a dinner table, as if paralysed. She begs Snape to help her. Voldemort point his wand at her, and a green light erupts out of its end. The light hits Charity, and she falls down on to the table dead, her eyes open and her face splattered with droplets of blood.
But when they went to Hogwarts, everything changed. The pair were parted when the Sorting Hat placed Severus in Slytherin and Lily in Gryffindor, and while Lily thrived in her new, magical life, Snape was essentially placed in close quarters with the likes of Lucius Malfoy, Avery and Mulciber.
Rose Granger-Weasley was the daughter of Ron Weasley and Hermione Granger. She attended Hogwarts for the first time in the same year as Albus Potter and Scorpius Malfoy. Unlike the boys, Rose was sorted into Gryffindor, following in the footsteps of her parents.
Confirmed are Lavender Brown (pureblood), Hermione Granger (the ONLY confirmed female Muggleborn), and Parvati Patil (at least half-blood per Year 7 Rule). So through some careful sleuthing, we can deduce that the Two Lost Gryffindor Girls are Lily Moon and Sophie Roper.
Are there any marriages between a Gryffindor and a Slytherin in the Harry Potter Canon? It's only implied, but Septimus Weasley, Arthur Weasley's father, married Cedrella Black. Sirius tells us that everyone in the Black family was Slytherin. Given how every Weasley was a Gryffindor, we can assume that so was Septimus.
Ron's becoming a prefect is designed to give him self-confidence which he has lacked to this point. Ron, an average wizard, feels overshadowed by the alarmingly competent Hermione and the famous Harry Potter, despite their being his best friends.
Hermione Granger was a sensible prefect, and took the role very seriously. Ron Weasley was a little less serious about it, to the point of neglecting several rules. In fact, he was extremely surprised to be chosen as a prefect as he expected Professor Dumbledore would have chosen Harry.
Snape probably recommended him. Maybe, Dumbledore thought that Draco would stay close to him if he was made Prefect, so Dumbledore would be able to talk to him and persuade him to be a good person, and also make sure he doesn't turn to the Dark Side.