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Programming in School: Look Back to Move Forward

Published:01 June 2014Publication History
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Abstract

In this article, the development of the Swedish informatics curriculum during the 1970s, 1980s and 1990s is studied and described. The study’s design is inspired by the curriculum theory presented by Lindensjö and Lundgren [2000], who suggest using the concept of arenas (the arenas of enactment, transformation and realisation) when discussing curriculum development. Data collection in this study comprises activities and actors in the arenas of enactment and transformation. Collected data include contemporary articles, journals, reports, booklets, government documents and archived documents. Findings show that informatics education in Sweden evolved from primarily focusing on programming knowledge related to automatic data processing and offered exclusively in vocational education (the 1960s and 1970s) to later (early 1980s) being introduced in the upper secondary school curriculum under the heading Datakunskap. The enactment of the informatics curriculum in 1983 encompassed programming, system development and computing in relation to applied sciences and civics. Mathematics teachers did much of the experimental work. It is shown that the competencies of upper secondary school teachers at the time rarely corresponded to the demands of the subject (content knowledge, resources and pedagogical skills). Stereotypical examples were therefore developed to support teachers in instructing about the subject content. When implemented in the theoretical natural science-programme, system development/systemisation was transformed into a twofold issue, comprising vocational attributes and societal aspects of computer programming. The implementation of today’s informatics education, including programming in the curriculum, should draw from lessons learned from history. For a successful outcome, this study emphasises the necessity to understand 1) the common incentives for introducing computer programming in the curriculum, 2) the requirement for teachers’ pedagogical content knowledge and 3) the stakeholders’ role in the curriculum development process.

References

  1. Åke Andersson, 1970. Datorn i skolan (DIS): förstudie 1. Kungl. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  2. Arsac, J. 1985. Teaching programming. The role of programming in teaching informatics. In Proceedings of the IFIP TC3 Working Conference on Teaching Programming.Google ScholarGoogle Scholar
  3. Martin Bäck. 1982. Datorisering och datapolitik, Malmö: LiberFörlag {i samarbete med} Högsk. i Örebro.Google ScholarGoogle Scholar
  4. F. L. Bauer. 1975. Top-down teaching of informatics in secondary school. In Proceedings of the IFIP 2nd World Conference on Computers in Education.Google ScholarGoogle Scholar
  5. Lars-Eric Björk. 1974. Effekter av BASIC-programmering i gymnasieskolans årskurs 1 på elevernas numeriska färdigheter och attityder mot matematik. Lärarhögskolan, Malmö.Google ScholarGoogle Scholar
  6. Lars-Eric Björk. 1983. Datorns intåg i svenska skolan. Nämnaren 1, 32--33.Google ScholarGoogle Scholar
  7. Lars-Eric Björk. 1987. ADM-projektet : Några synpunkter på gymnasieskolans datakunskap. Uppsala.Google ScholarGoogle Scholar
  8. Lars-Eric Björk and Lennart Wendelöv. 1982. Datateknisk variant. Skolan och Datorn 3, 10--11.Google ScholarGoogle Scholar
  9. Lars-Eric Björk, Bo Loftrup, and Rolf Nilsson. 1975. An introductory computer programming course and some of its effects on the teaching of mathematics. In Proceedings of the IFIP 2nd World Conference on Computers in Education.Google ScholarGoogle Scholar
  10. Kenneth Borg. 1976. Några terminer vid en minidator. Nämnaren T, 122--124.Google ScholarGoogle Scholar
  11. Ivan Bratko, Vladislav Rajkovic, and B. Roblek. 1975. What should secondary school students know about computers: Analysis of an experiemnt. In Proceedings of the IFIP 2nd World Conference on Computers in Education. 841.Google ScholarGoogle Scholar
  12. Martin Bäck. 1982. Datorisering och datapolitik, Malmö: LiberFörlag {i samarbete med} Högsk. i Örebro.Google ScholarGoogle Scholar
  13. Douglas H. Clements and Dominic F. Gullo. 1984. Effects of computer programming on young children’s cognition. J. Educ. Psych. 76, 6, 1051--1058.Google ScholarGoogle ScholarCross RefCross Ref
  14. F. Michael Connelly and Shijing J. Xu. 2010. Curriculum Development - evaluation and research: An overview of research in curriculum inquiry. In International Encyclopedia of Education 3rd Ed., E. Baker, B. McGaw and P. Peterson Eds., Elsevier, 324--334.Google ScholarGoogle Scholar
  15. Jere Confrey. 1990. A review of the research on student conceptions in mathematics, science, and programming. Rev. Research Educ. 16, 3--56.Google ScholarGoogle ScholarCross RefCross Ref
  16. Valentina Dagiene. 2005. Teaching information technology in general education: Challenges and perspectives. In From Computer Literacy to Informatics Fundamentals International Conference on Informatics in Secondary Schools -- Evolution and Perspectives (ISSEP ’05), Lecture Notes in Computer Science, vol. 3422, 53--64. Google ScholarGoogle ScholarDigital LibraryDigital Library
  17. Department for Education. 2013. The National Curriculum in England: Framework Document for Consultation.Google ScholarGoogle Scholar
  18. Ecklesiastikdepartementet. 1965. SOU 1965:56. Fackutbildning i automatisk databehandling: betänkande avgivet av ADB-utbildningssakkunniga.Google ScholarGoogle Scholar
  19. Kerstin Ekstig, Göran Nydahl, and Klas Öhman. 1989. Programmering i DPG-prolog. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  20. Martin Emanuel. 2009. Folkbildning kring datorn 1978--85: Transkript av ett vittnesseminarium vid tekniska museet i stockholm den 9 oktober 2008. Avdelningen för teknik- och vetenskapshistoria, KungligaTekniska högskolan, Stockholm.Google ScholarGoogle Scholar
  21. Lil Engström. 1991. Vad är datakunskap? Datorn i Utbildningen 5, 50--51.Google ScholarGoogle Scholar
  22. Peter Fagerström. 1973. Datorn i skolkommunen (DISK): Kartläggning, beskrivning. förslag till åtgärder. Linköping.Google ScholarGoogle Scholar
  23. Matthias Felleisen and Shriram Krishnamurthl. 2009. Viewpoint: Why computer science doesn’t matter. Commun. ACM 52, 7, 37--40. Google ScholarGoogle ScholarDigital LibraryDigital Library
  24. Steve Furber. 2012. Shut down or restart? The way forward for computing in UK schools. Royal Society, London.Google ScholarGoogle Scholar
  25. Governmental bill 1980/81:UbU22 (betänkande) med anledning av proposition 1980/81:100 såvitt gäller anslag till driften av grundskolor m.m. och gymnasieskolor, m.m. jämte motioner, 28--29.Google ScholarGoogle Scholar
  26. Governmental bill 1980/81:969 by Lena Hjelm-Wallén and Christina RogestamGoogle ScholarGoogle Scholar
  27. Barbro Grevholm. 1991. Räknegrottan : Datorn som pedagogiskt hjälpmedel : Rapport från en treårig försöksverksamhet inom ramen för DOS (datorn och skolan).Google ScholarGoogle Scholar
  28. Michael Griffiths, and E. D. Tagg. 1985. The role of programming in teaching informatics. In Proceedings of the IFIP TC3 Working Conference on Teaching Programming.Google ScholarGoogle Scholar
  29. J. Hebenstreit. 1985. Teaching programming to everybody why? to whom? what? In The Role of Programming in Teaching Informatics. Proceeding of the IFIP TC3 Working Conference on Teaching Programming. Google ScholarGoogle ScholarDigital LibraryDigital Library
  30. Dennis R. Herschbach. 1992. Technology and efficiency: Competencies as content. J. Tech. Educ. 3, 2, 15--25.Google ScholarGoogle ScholarCross RefCross Ref
  31. Mark Hoffman and Jonathan Blake. 2003. Computer literacy: Today and tomorrow. J. Comput. Sci. Colleges 18, 5, 221--233. Google ScholarGoogle ScholarDigital LibraryDigital Library
  32. Peter Hubwieser. 2012. Computer science education in secondary schools -- The introduction of a new compulsory subject. ACM Trans. Comput. Educ. 12, 4, Article 16. Google ScholarGoogle ScholarDigital LibraryDigital Library
  33. Peter Hubwieser, Michal Armoni, Torsten Brinda, Valentina Dagiene, Ira Diethelm, Michail N. Giannakos, Maria Knobelsdorf, Johannes Magenheim, Roland Mittermeir, and Sigrid Schubert. 2011. Computer science/informatics in secondary education. In Proceedings of the 16th Annual Conference Reports on Innovation and Technology in Computer Science Education (ITiCSE-WGR’11). Google ScholarGoogle ScholarDigital LibraryDigital Library
  34. Huvudmannaskapskommittén. 1980. Förändrat huvudmannaskap för ADB-linjen: ett delbetänkande från Huvudmannaskapskommittén. LiberFörlag/Allmänna förlaget, Stockholm.Google ScholarGoogle Scholar
  35. Charles L. Isbell, Lynn Andrea Stein, Robb Cutler, Jeffrey Forbes, Linda Fraser, John Impagliazzo, Viera Proulx, Steve Russ, Richard Thomas, and Yan Xu. 2010. (Re)defining computing curricula by (re)defining computing. SIGCSE Bull. 41, 4, 195--207. Google ScholarGoogle ScholarDigital LibraryDigital Library
  36. Gunilla Jedeskog, Birgitta Hyltén, and Ulla Riis. 1991. Skolan och datorn : Datorn som pedagogiskt hjälpmedel : En sammanställning av resultat och erfarenheter från 130 skolrapporter och projektledarenkäter. Linköping.Google ScholarGoogle Scholar
  37. Lennart Karlsson. 1977. Våra erfarenheter från försöksverksamheten med DIS-projektet ht7-76. Nämnaren 4, 33--35.Google ScholarGoogle Scholar
  38. Herbert M. Kliebard. 1992. Constructing a history of the American curriculum. In Handbook of research on curriculum, P. Jackson Ed., Macmillan, New York, 157--184.Google ScholarGoogle Scholar
  39. Donald E. Knuth. 1974. Structured programming with go to statements. ACM Comput. Surv. 6, 4, 261--301. Google ScholarGoogle ScholarDigital LibraryDigital Library
  40. Anita Kollerbaur. 1977. Datorn i skolan - DIS-projektet. Nämnaren T, 18--24.Google ScholarGoogle Scholar
  41. Yuen-Kuang C. Liao and George W. Bright. 1991. Effects of computer programming on cognitive outcomes: A meta-analysis. J. Educ. Comput. Research 7, 3, 251--266.Google ScholarGoogle ScholarCross RefCross Ref
  42. Börje Langefors. 1976. Datorer och skolan. Nämnaren, T, 13--17.Google ScholarGoogle Scholar
  43. Yngve Lindberg. 1987. Vad händer på SÖ? Gymnasieskolan. Nämnaren 1, 8.Google ScholarGoogle Scholar
  44. Sverker Lindblad and Thomas S. Popkewitz. 2000. Public discourses on education governance and social integration and exclusion: analyses of policy texts in European contexts. Department of Education, Uppsala University, Uppsala.Google ScholarGoogle Scholar
  45. Bo Lindensjö and Ulf P. Lundgren. 2000. Utbildningsreformer och politisk styrning. Stockholm: HLS förl.Google ScholarGoogle Scholar
  46. Arthur Luerhmann. 1980. Computer literacy: a national crisis and a solution for it. Byte 5, 98--102.Google ScholarGoogle Scholar
  47. Sixten Marklund. 1987. Skolsverige 1950--1975. D. 5, läroplaner. Stockholm: Liber/Utbildningsförl.Google ScholarGoogle Scholar
  48. Richard E. Mayer. 1975. Different problem-solving competencies established in learning computer programming with and without meaningful models. J. Educ. Psych. 67, 6, 725--734.Google ScholarGoogle ScholarCross RefCross Ref
  49. Peter Micheuz. 2005. 20 Years of computers and informatics in Austria’s secondary academic schools. In Proceedings of the International Conference on Informatics in Secondary Schools: Evolution and Perspectives (ISSEP’05). R. Mittermeir Ed., 3422, 20--31. Google ScholarGoogle ScholarDigital LibraryDigital Library
  50. Modern datateknik. 1966a. De första ADB-lärarna, 6, 16--17. Stockholm: Fackpressförlaget.Google ScholarGoogle Scholar
  51. Modern datateknik. 1966b. Höstens ADB-undervisning: Går ni på Högskola eller kör ni med bandspelare?, 6, 32--33. Stockholm: Fackpressförlaget.Google ScholarGoogle Scholar
  52. Barbee T. Mynatt, Kirk H. Smith, Anita L. Kamouri, and Teresa A. Tykodi. 1986. Which way to computer literacy, programming or applications experiences. Int. J. Man-Mach. Stud. 25, 5, 557--572. Google ScholarGoogle ScholarDigital LibraryDigital Library
  53. Jörgen Nissen, Ulla Riis, and Birgitta Hyltén. 1991. Skolan och datorn : Delrapport 2 : Besök våren 1991 vid 23 skolor som bedriver försök med datorn som pedagogiskt hjälpmedel. Linköping: Univ.Google ScholarGoogle Scholar
  54. Istvan P. Orci. 1983. PROLOG: framtidens programspråk? Skolan och Datorn 3, p. 12, 25.Google ScholarGoogle Scholar
  55. David P. and Palumbo, B. 1990. Programming Language/Problem-Solving Research: A Review of Relevant Issues. Rev. Educ. Research 60, 1, 65--89.Google ScholarGoogle ScholarCross RefCross Ref
  56. Seymour Papert. 1980. New cultures from new technologies. Byte 5, 230--240.Google ScholarGoogle Scholar
  57. Roy D. Pea and Midian Kurland. 1984. The cognitive effects of learning computer programming. New Ideas Psych. 2, 2, 137--168.Google ScholarGoogle ScholarCross RefCross Ref
  58. William F. Pinar, William M. Reynolds, Patrick Slattery, and Peter M. Taubman. 1995. Understanding Curriculum: An Introduction to the Study of Historical and Contemporary Curriculum Discourses. New York: P. Lang.Google ScholarGoogle Scholar
  59. Proposition 1980/81:100 Bilaga 10. Budgetproposition, utbildningsdepartementet. Norstedts Tryckeri, Stockholm.Google ScholarGoogle Scholar
  60. Proposition 1982/83:100 Bilaga 10. Budgetproposition, utbildningsdepartementet. Norstedts Tryckeri, Stockholm.Google ScholarGoogle Scholar
  61. Proposition 1984/85:100 Bilaga 10, Ubu 19, rskr.273.Google ScholarGoogle Scholar
  62. Proposition 1984/85:220 “Om datapolitik”. Stockholm: Norstedts Tryckeri.Google ScholarGoogle Scholar
  63. Proposition 1987/88:100 Bilaga 10, p. 59. Budgetproposition, utbildningsdepartementet. Norstedts Tryckeri, Stockholm.Google ScholarGoogle Scholar
  64. RA. Documents in the National Archives of Sweden (Swedish: Riksarkivet, RA).Google ScholarGoogle Scholar
  65. Ulla Riis. 1991. Skolan och datorn : Satsningen datorn som pedagogiskt hjälpmedel 1988--1991. Linköping: Univ., Tema Teknik och social förändring.Google ScholarGoogle Scholar
  66. Lennart Rolandsson. 2011. Teacher pioneers in the introduction of computing technology in Swedish upper secondary school. In Proceedings of the 3rd IFIP WG 9.7 Conference on History of Nordic Computing.Google ScholarGoogle ScholarCross RefCross Ref
  67. Lennart Rolandsson. 2012. Changing computer programming education; the dinosaur that survived in school: an explorative study of educational issues based on teachers’ beliefs and curriculum development in secondary school. Ph.Lic. Dissertation (summary). Kungliga Tekniska högskolan, Stockholm.Google ScholarGoogle Scholar
  68. Mara Saeli, Jacob Perrenet, Wim M. G. Jochems, and Bert Zwaneveld. 2011. Teaching programming in secondary school: A pedagogical content knowledge perspective. Informatics Educ. 10, 1, 73--88.Google ScholarGoogle ScholarCross RefCross Ref
  69. Sue Sentance, Mark Dorling, and Adam McNicol. 2013. Computer science in secondary schools in the UK: Ways to empower teachers. In Informatics in Schools. Sustainable Informatics Education for Pupils of all Ages, I. Diethelm and R. T. Mittermeir Eds., Springer, 115--126. Google ScholarGoogle ScholarDigital LibraryDigital Library
  70. Skolöverstyrelsen. 1975. Specialinformation. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  71. Skolöverstyrelsen. 1980. Datorn i skolan: DIS: SÖ:s handlingsprogram och slutrapport SÖ-projekt 628. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  72. Skolöverstyrelsen. 1981. PRODIS : programvara och datorutrustning i skolan : slutrapport SÖ-projekt 6205. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  73. Skolöverstyrelsen. 1983. Läroplan för gymnasieskolan. 2, Supplement, 95, Datakunskap. LiberUtbildningsförlag, Stockholm.Google ScholarGoogle Scholar
  74. Skolöverstyrelsen. 1984. Utbildningen inför datasamhället. Utgångspunkter och inriktning. Skolövertyrlesen, Stockholm.Google ScholarGoogle Scholar
  75. Skolöverstyrelsen. 1987. K-man rapporten : Försöksverksamhet med systemutvecklingsverktyg i ADB-undervisningen i gymnasieskolan. Skolöverstyrelsen, Stockholm.Google ScholarGoogle Scholar
  76. Skolverket. 1998. Läroplan för förskolan, LPFö98. Skolverket. Stockholm.Google ScholarGoogle Scholar
  77. Skolverket. 2011. Läroplan för grundskolan, förskoleklassen och fritidshemmet 2011. Skolverket. Stockholm.Google ScholarGoogle Scholar
  78. Skolverket. 2012. Upper secondary school 2011. Skolverket, Stockholm.Google ScholarGoogle Scholar
  79. Skolverket. 2013. IT-användning och it-kompetens i skolan. Rapport 386. Skolverket, Stockholm.Google ScholarGoogle Scholar
  80. Anders Söderlund. 2000. Det långa mötet - IT och skolan : Om spridning och anammande av IT i den svenska skolan. Luleå.Google ScholarGoogle Scholar
  81. SOU 2008:109. 2008. Utredningen om en ny lärarutbildning. En hållbar lärarutbildning: betänkande. Fritze, Stockholm.Google ScholarGoogle Scholar
  82. SOU 2014:13. 2014. Delbetänkande av Digitaliseringskommissionen. En digital agenda i människans tjänst - en ljusnande framtid kan bli vår. Fritze, Stockholm.Google ScholarGoogle Scholar
  83. Hans Svensson. 1985. He who can does, he who cannot teaches basic. Skolan och Datorn 2, 14--15.Google ScholarGoogle Scholar
  84. Maciej M. Syslo and Anna Beata Kwiatkowska. 2008. The challenging face of informatics education in Poland. Informatics education: Supporting computational thinking. In Proceedings of the 3rd International Conference on Informatics in Secondary Schools: Evolution and Perspectives (SSEP’08), Lecture Notes in Computer Science, vol. 5090, 1--18. Google ScholarGoogle ScholarDigital LibraryDigital Library
  85. Wladyslaw M. Turski. 1973. Programming teaching techniques. In Proceedings of the IFIP Working Conference on Programming Teaching Techniques.Google ScholarGoogle Scholar
  86. Utbildningsdepartementet. 1977. Skolöverstyrelsens författningssaml.: SÖ-FS 1977:13. LiberLäromedel/ Utbildningsförlaget, Stockholm.Google ScholarGoogle Scholar
  87. Utbildningsdepartementet. 1978. Skolöverstyrelsens författningssaml.: SÖ-FS 1978:194. LiberLäromedel/ Utbildningsförlaget, Stockholm.Google ScholarGoogle Scholar
  88. Utbildningsdepartementet. 1979. Skolöverstyrelsens författningssaml.: SÖ-FS 1979:107. LiberLäromedel/ Utbildningsförlaget, Stockholm.Google ScholarGoogle Scholar
  89. Utbildningsdepartementet. 1982. Skolöverstyrelsens författningssamling: SÖ-FS 1982:21. LiberLäromedel/Utbildningsförlaget, Stockholm.Google ScholarGoogle Scholar
  90. Utbildningsdepartementet. 1986a. DsU 1986:10. Handlingsprogram för datautbildning i skola, vuxenutbildning och lärarutbildning. Liber, Stockholm.Google ScholarGoogle Scholar
  91. Utbildningsdepartementet. 1986b. Datautbildningsgruppen. Handlingsprogram för datautbildning i skola, vuxenutbildning och lärarutbildning. Liber/Allmänna förlaget, Stockholm (English: Program of Action for Computer Education in Schools, Extension Studies and Teacher Training).Google ScholarGoogle Scholar
  92. Utbildningsdepartementet. 1988. Försöksverksamhet med prolog i undervisningen vid gymnasieskolan. Utbildningsdepartementet, Stockholm.Google ScholarGoogle Scholar
  93. Utbildningsdepartementet. 198n. Programutveckling: Metoder och hjälpmedel. Utbildningsdepartementet, Stockholm.Google ScholarGoogle Scholar
  94. Utbildningsdepartementet. 1994. 1994 års läroplan för de frivilliga skolformerna, Lpf 94: Särskilda programmål för gymnasieskolans nationella program ; kursplaner i kärnämnen för gymnasieskolan och den gymnasiala vuxenutbildningen. Utbildningsdepartementet, Fritze, Stockholm.Google ScholarGoogle Scholar
  95. Olle Vejde. 1984. Några fakta om NUMA försöket. Nämnaren 2, 40.Google ScholarGoogle Scholar
  96. Magnus Vik. 1992. Från räknegrottan till shejkens val : En utvärdering ur ekonomiskt perspektiv av ett försök att i central regi driva programvaruutveckling för ungdomsskolan.Google ScholarGoogle Scholar
  97. Cameron Wilson, Leigh A. Sudol, Chris Stephenson, and Mark Stehlik. 2010. Running on empty. Executive summary. http://csta.acm.org/runningonempty/fullreport.pdf.Google ScholarGoogle Scholar
  98. Joseph Weizenbaum. 1984. Another view from MIT. Byte 9, 225.Google ScholarGoogle Scholar
  99. Lennart Wendelöv. 1980. Fortbildning i datalära. mer tid för matematik. remissvar på kursplaneförslag för NT-linjerna. Nämnaren 3, 7--11.Google ScholarGoogle Scholar
  100. Lennart Wendelöv and Lars-Eric Björk. 1981. Datateknisk variant. Skolan Och Datorn 2, 3.Google ScholarGoogle Scholar
  101. Lennart Wettstam. 1982. Datateknisk variant i ny gestalt. Skolan och Datorn 4, 2.Google ScholarGoogle Scholar
  102. Lennart Wettstam. 1982. Datavariant på samhällsvetenskaplig linje. Skolan och Datorn 4, 6.Google ScholarGoogle Scholar
  103. Lennart Wettstam. 1984. Datakunskap. Nämnaren 2, 12.Google ScholarGoogle Scholar
  104. John Woollard. 2005. The implications of the pedagogic metaphor for teacher education in computing. Technology, Pedagogy and Education 14, 2, 189--204.Google ScholarGoogle ScholarCross RefCross Ref

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      cover image ACM Transactions on Computing Education
      ACM Transactions on Computing Education  Volume 14, Issue 2
      Special Issue on Computing Education in (K-12) Schools
      June 2014
      180 pages
      EISSN:1946-6226
      DOI:10.1145/2642651
      Issue’s Table of Contents

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      Publication History

      • Published: 1 June 2014
      • Accepted: 1 April 2014
      • Revised: 1 March 2014
      • Received: 1 March 2013
      Published in toce Volume 14, Issue 2

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