Nastily Exhausting Wizarding Test

A Nastily Exhausting Wizarding Test (often abbreviated N.E.W.T.) is a subject-specific exam that seventh year witches and wizards at Hogwarts School of Witchcraft and Wizardry take to help them pursue certain careers after their graduation. For instance the Ministry of Magic only accepts Auror applicants with at least five N.E.W.T.s with top grades of either "Outstanding" or "Exceeds Expectations".

Overview
At Hogwarts School of Witchcraft and Wizardry, pupils have to complete the Ordinary Wizarding Level exams before selecting the subjects they want to continue for N.E.W.T. level, which is the highest merit that they can achieve. They pick the subjects at the start of their sixth year, providing they achieved the O.W.L. grades that the teachers want them to have, and providing there is sufficient demand in the case of specialised subjects (such as Alchemy).

They study for their N.E.W.T.s in the sixth and seventh year, before sitting an exam for each subject at the end of the seventh and final year. The exams themselves are incredibly difficult as stated in the name "nastily exhausting".

It is vital they achieve a high grade, as many professions will require them. Pupils do not have to sit their N.E.W.T.s if they don't want to.

Advancing to N.E.W.T. classes
"I do not accept students into N.E.W.T. classes unless they have achieved 'Exceeds Expectations' or higher at Ordinary Wizarding Level."

- Professor McGonagall on the increased difficulty in N.E.W.T.

A student must have previously achieved an O.W.L. in the subject in order to move on to N.E.W.T.-level classes. More specialised subjects (such as Alchemy) are available with sufficient demand and a required minimum of O.W.L.s. Most Hogwarts Professors will accept an 'Exceeds Expectations' on the student's O.W.L.s for those classes in order to allow them to advance to N.E.W.T.-level. However, some professors like Severus Snape, would only let students with an 'Outstanding' in their O.W.L. pass through to his Potions N.E.W.T. class, although he did accept students with 'Exceeds Expectations' into his N.E.W.T.-level DADA class during the 1996–1997 school year.

It is unknown what the limit is for how many subjects the pupil may sit at N.E.W.T. level. Hermione Granger was granted seven, while Harry Potter and Ronald Weasley picked five.

Others

 * Albus Dumbledore and Minerva McGonagall were said to have earned top grades, likely in at least Transfiguration since they both taught the subject.
 * Severus Snape likely achieved a high grade in Potions since he later taught the subject.
 * Barty Crouch Jr achieved twelve O.W.L grades and likely achieved N.E.W.T grades too.
 * Percy Weasley graduated with perfect N.E.W.T grades.
 * Tom Riddle was said to have achieved an Outstanding in every exam that he took.
 * Hermione Granger returned to take her N.E.W.T.s despite not attending her seventh year at Hogwarts at the time she should have. She probably continued with the subjects she picked at the start of her sixth year; Charms, Defence Against the Dark Arts, Herbology, Transfiguration, Arithmancy, Ancient Runes and Potions.
 * Bill Weasley and Charlie Weasley likely achieved high N.E.W.T grades, probably in at least Charms and Care of Magical Creatures given their careers.
 * Lily Potter, James Potter and Remus Lupin likely achieved high grades given that they were exemplary students.
 * Arthur Weasley in at least Muggle Studies, Dolores Umbridge and many other Ministry of Magic employees. The majority of jobs at the Ministry will want N.E.W.T. grades.
 * Hogwarts professors have likely achieved N.E.W.T.s in at least in their own subject. An exception may be Neville Longbottom, who left Hogwarts to be an Auror and later became Herbology professor.

Known leavers
It's the choice of every student whether they want to take their N.E.W.T.s or not, and not everyone will pass. There are many jobs who will accept applicants who only have O.W.L. grades but it helps to have N.E.W.T.s. and many high profile jobs will prefer them. Every student tries to return for the final two years.

However, Fred and George Weasley, for example, did not bother taking the N.E.W.T.s and left Hogwarts to set up a joke shop. However, it should be noted that the immediate cause of their departure was to mainly to evade the much-despised Professor Umbridge, and not because they simply decided not to achieve them.

Behind the scenes

 * The N.E.W.T. is comparable to the Muggle A-Levels given at a similar stage of education in most of the UK and Commonwealth, the leaving certificate given in Ireland, the Advanced Placement exams given in the United States, the Australian Certificate of Education (overriding State certificates in 2014) given in Australia, or the International Baccalaureate Diploma Programme given worldwide.
 * Harry Potter, Ron Weasley, and Hermione Granger skipped the 1997–1998 school year, which would have been their final year, due to the reign of Lord Voldemort and their search for his Horcruxes. Presumably, Muggle-born students also missed their schooling that year. After the defeat of Voldemort, Hermione completed her education and took her N.E.W.T.s, while Harry became an Auror and Ron initially became an Auror and then left to help his brother George at Weasleys' Wizard Wheezes. Those who participated in the Battle of Hogwarts were given exemptions from usual Auror qualifications by Kingsley Shacklebolt due to their duelling experience.
 * Doing well on N.E.W.T.s is normally imperative to earning a position at the Ministry of Magic, except under special circumstances (see above).
 * N.E.W.T.s are the highest level of examinations given at Hogwarts. It is unknown what system other wizarding schools such as Beauxbatons or Durmstrang use.
 * It is assumed that the name, N.E.W.T., is a play on words (like the O.W.L.s), because owls and newts are both animals.
 * It is possible that Katie Bell did not take her N.E.W.T.s as she was hospitalised for most of her seventh year. If this is the case, then this would explain as to why Katie attended Hogwarts in both parts of the Deathly Hallows film.

Notes and references
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