Nastily Exhausting Wizarding Test

A Nastily Exhausting Wizarding Test (often abbreviated N.E.W.T.) is a subject-specific exam that seventh year wizards and witches 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
The N.E.W.T. exams are the highest level tests that Hogwarts School of Witchcraft and Wizardry offer to students. The exams themselves are incredibly difficult as stated in the name "nastily exhausting". At the end of their seventh and final year, students take the N.E.W.T. exams, which test what the student has learned over the past two years. Many professions require high grades in these tests, meaning that students must work hard to ensure that they pass. Not all students take or even pass N.E.W.T.s.

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. Most Hogwarts Professors will accept an 'Exceeds Expectations' on the student's O.W.L. for a class 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. This may or may not have been at the prompting of Professor Dumbledore.

Aurors

 * Gawain Robards
 * John Dawlish
 * Proudfoot
 * Savage
 * Williamson

Healers

 * Dilys Derwent
 * Lancelot
 * Augustus Pye
 * Hippocrates Smethwyck
 * Helbert Spleen
 * Miriam Strout

Others

 * Most likely others who worked for the Ministry of Magic, such as Arthur Weasley, Mafalda Hopkirk, Amelia Bones, and Dolores Umbridge.
 * Hogwarts Professors most likely have taken N.E.W.T.s, at least in their own subject

Notable students who didn't take N.E.W.T.s
Not all wizards pass or even take the N.E.W.T.s, as they can find other jobs using their O.W.L. results. 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 evade the much-despised Professor Umbridge, and that the aim of most students was always to return for the final two years.

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 helped his brother George at Weasleys' Wizard Wheezes, and then also became an Auror. 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, 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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