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Theodor Haagaas

Theodor Haagaas is a mathematics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Theodor Haagaas rather than just read about it. In short: Theodor Christian Petersen Haagaas (15 June 1873, Tistedalen – 25 December 1961, Oslo) was a Norwegian mathematician, mathematics educator and private school owner. He was the founder and owner of the Haagaas School, a private gymnasium at Frogner, Oslo that existed 1915–1955.

Theodor Haagaas — main illustration
Theodor Haagaas — illustration

Key takeaways

  • Theodor Haagaas belongs to mathematics; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Theodor Haagaas to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Theodor Haagaas from memory before moving on to harder problems.

Reference excerpt

Theodor Christian Petersen Haagaas (15 June 1873, Tistedalen – 25 December 1961, Oslo) was a Norwegian mathematician, mathematics educator and private school owner. He was the founder and owner of the Haagaas School, a private gymnasium at Frogner, Oslo that existed 1915–1955. Haagaas School was Norway's best known intensive gymnasium or "student factory" (Norwegian: studentfabrikk) in the first half of the 20th century, in the tradition of the historical Heltberg School of the 19th century; the noted educator Mosse Jørgensen wrote that "if any school had deserved the epithet 'The New Heltberg', it was Haagaas School." He was also a co-owner of Frogner School and Nissen's Girls' School, and taught mathematics at Frogner School for nearly half a century. He was the author of the widely used Haffner og Haagaas series of textbooks in mathematics, which was published between 1925 and 1979 in dozens of editions and which was the most widely used series of mathematics textbooks in Norway for a large part of the 20th century. He was described as a distinctive and unconventional teacher with a keen sense of humor, and as the country's best-known mathematics educator. Upon his passing, he was described by Aftenposten as "a very widely known Norwegian educator." He received the King's Medal of Merit in Gold in 1949 for his services to education in Norway. Among his four daughters was the humanist and resistance fighter Henriette Bie Lorentzen.

Background

He grew up in Tistedalen outside Frederikshald. His father Theodor Christian Haagaas (1823–1899) was the sawmill director (1862–1892) of Norway's largest timber company, Saugbrugsforeningen, and a shipowner; the elder Theodor was born on the farm Haagaas (from Old Norse Haukáss, "hawk hill") in Trøgstad, which his family had owned at least since 1555. His mother Nora was born in Norway to Swedish immigrant parents of Forest Finnish heritage, and died early. His father later lived at Veden Manor, which had previously belonged to Theodor's maternal grandfather. Theodor Haagaas was one of the pioneers of skiing in Tistedalen around 1885–1886. In 1908 he married his former pupil Henriette Wegner Paus (1879–1942), a university-educated teacher at Nissen's Girls' School. She was the daughter of Bernhard Pauss and Henriette Pauss (née Wegner), major figures in the development of girls' education in Norway and long-time owners and leaders of Nissen's Girls' School, and the granddaughter of the mining magnate Benjamin Wegner and the banking heir and philanthropist Henriette Wegner. His wife was a goddaughter of Wilhelm Adelsten Maribo. Theodor and Henriette were the parents of four daughters, among them the journalist, humanist and resistance fighter Henriette Bie Lorentzen (née Henriette Wegner Haagaas). A blue plaque, placed by Oslo Byes Vel, commemorates his daughter Henriette at Riddervolds gate 9, where the family lived from 1912. He was the uncle of the publisher Henrik Groth and the brother-in-law of Nikolai Nissen Paus, George Wegner Paus and Augustin Paus.

Career

He attended the Frederikshald Gymnasium and graduated with the examen artium university entrance exam in 1891. He subsequently studied philosophy, mathematics, natural sciences and law at the Royal Frederick University. He also served as a lieutenant in the Royal Norwegian Navy 1898–1902. From 1900 he was a lecturer in mathematics at the private gymnasium Frogner School in Oslo. In 1911 he became a member of the management of the school and in 1913 he became one of the school's co-owners. At the time Frogner School's neighbour, the Nissen's Girls' School, was also owned by Frogner School, although they operated as separate schools. He and the other owners sold both schools to Christiania municipality in 1918 and continued to manage them until 1919. In 1917 he was appointed by the King-in-Council as a lecturer at Drammen Higher School, and took office in 1918. In 1920 he left this position to become a lecturer at Frogner School again. In 1915 he founded Haagaas School, a private gymnasium in Oslo that existed until 1955, and was the school's headmaster until 1946. Haagaas School was the last school in Norway in the tradition of the Heltberg School of the 19th century, offering a fast track to the examen artium (a so-called studentfabrikk, "student factory" or intensive gymnasium). The noted educator Mosse Jørgensen wrote that "if any school had deserved the epithet 'The New Heltberg', it was Haagaas School." According to his former pupil Harald Throne-Holst, Haagaas was characterized by a "strong and active sense of humor." The journal Den høgre skolen (The Higher School) noted that:

Throughout his teaching career, he worked primarily at Frogner School in Oslo, where he was a central and unifying figure ... his main subject was mathematics. All of his students remember him as an outstanding teacher; they feared and loved him, and they reveled in his incomparable humor. He must have been the ideal math teacher. He possessed great authority, was conscientious and meticulous, practical and down-to-earth, patient, clear, and concise. And he had a sense of humor! Along with all these qualities, he was also quite the humanist – a humanist of the classical type. He was a co-author and subsequently the sole author of the Haffner og Haagaas series of textbooks in mathematics, which was published between 1925 and 1979 in numerous editions. He was one of the handful of government-appointed examiners in mathematics at the examen artium university entrance exams for several decades. On his death he was described by Aftenposten as a "very widely known educator."

Quotes "Latin, it is mathematics, language mathematics" "If we have two twins and one is named Clariss and the other is named Magdalena, and we say that Clariss equals Magdalena, then that is an equation." "We cannot afford to spend education on the lazy"

Honours King's Medal of Merit in Gold, 1949, for services to education and for fostering culture and Bildung in wide circles of society

References

Illustrations

Theodor Haagaas illustration
Theodor Haagaas: A blue plaque, placed by Oslo Byes Vel, commemorates his daughter Henriette Bie Lorentzen at Riddervolds gate 9, where the family lived from 1912
A blue plaque, placed by Oslo Byes Vel, commemorates his daughter Henriette Bie Lorentzen at Riddervolds gate 9, where the family lived from 1912
Theodor Haagaas: His wife Henriette (second from left) with her siblings Louise, Augustin, Nikolai and George, photographed by Gustav Borgen
His wife Henriette (second from left) with her siblings Louise, Augustin, Nikolai and George, photographed by Gustav Borgen
Theodor Haagaas: The shared building of Frogner School and Haagaas School at Frogner, Oslo
The shared building of Frogner School and Haagaas School at Frogner, Oslo
Theodor Haagaas: Grave at Vestre gravlund
Grave at Vestre gravlund

Worked examples

Example 1 — a first encounter with Theodor Haagaas

Start with the simplest possible case. Write down what Theodor Haagaas claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In mathematics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Theodor Haagaas before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Theodor Haagaas ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Theodor Haagaas

In research
Theodor Haagaas appears in mathematics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Theodor Haagaas in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Theodor Haagaas is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1873 births, 1961 deaths, Burials at Vestre gravlund, so understanding it makes those chapters shorter.
In everyday life
Look for Theodor Haagaas outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Theodor Haagaas in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Theodor Haagaas means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Theodor Haagaas out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Theodor Haagaas in simple terms?

Theodor Christian Petersen Haagaas (15 June 1873, Tistedalen – 25 December 1961, Oslo) was a Norwegian mathematician, mathematics educator and private school owner. He was the founder and owner of the Haagaas School, a private gymnasium at Frogner, Oslo that existed 1915–1955.

Why does Theodor Haagaas matter?

Because it connects several mathematics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Theodor Haagaas?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Theodor Haagaas.

Tags

  • 1873 births
  • 1961 deaths
  • Burials at Vestre gravlund
  • Heads of schools in Norway
  • Norwegian mathematics educators
  • Norwegian people of Forest Finnish descent
  • Norwegian people of Swedish descent
  • People from Halden
  • Recipients of the King's Medal of Merit in gold
  • Royal Norwegian Navy personnel
  • Schoolteachers from Oslo
  • Scientists from Oslo

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