Bad Computer Science in Beginners Programming Courses:

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• Bad Computer Science in Beginners Programming
  Courses
• Considered Harmful?
• A case study of the Tufts graphical programming
  language
• John Murnane and Anne McDougall

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• ICT In Education and Research Group
• Faculty of Education
• The University of Melbourne

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The Lego RCX and Tower
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Buggy
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Control Lab
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TC Lego Interface Box
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(No Transcript)
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Tufts Programming
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Buggy program
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Traffic lights
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Mother-tongue

• Gal-Ezer and Harel
• Communications of the ACM

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Edsger Dijkstra

• It is practically impossible to teach good
  programming to students that have had prior
  exposure to BASIC. As potential programmers they
  are mentally mutilated beyond hope of
  regeneration.

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Declaration

• Robotics at Melbourne 1982 2005
• Jon Pearce 19821995
• Me 19962005.
• So, ten years of experience.
• Robotics is fun and it works, no matter what the
  system.

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Names

• The warning message we sent the Russians was a
  calculated ambiguity that would be clearly
  understood.
• General Alexander Haig

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Names /

• The creation and creative use of names in a
  program has significance beyond the immediate
  Computer Science involved.
• Tufts does not allow the programmer to name things

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Control Structures

• The go to statement as it stands is just too
  primitive it is too much an invitation to make a
  mess of ones program.
• Edsger Dijkstra

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Graphical Languages

• All the advantages and disadvantages of a Flow
  chart.

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(No Transcript)
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Tufts and the Goto
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All the advantages of Dartmouth BASIC

• It is easy to learn.
• Beginners find it simple to write novice-level
  programs.
• Inexperienced teachers will find it far more
  attractive than a language such as Logo.
• Students can generate real enthusiasm with early,
  practical success.

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Defense against errors and debugging

• Bottom-up programming, rather than top-down
  design and modification.
• Procedures cannot be tested independently.
• Harder to alter than text.
• (RCX programs hard to debug.)

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Information hiding

• Information not specifically required to be
  passed from one program module to another should
  be invisible and inaccessible outside it
• The process of information transmission should be
  manifest
• RCX 1.0 32 Global variables.
• (RCX 2.0 does allow local variables.)

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Objects

• The Tufts programming environment is very modern
  and object-oriented
• The programs created with it are not.
• (Double-clicking an object does not bring up its
  associated attributes window. It brings up its
  Help-box.)

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Recursion

• Doesnt work

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Conclusion

• As teachers, we have a problem

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Thank you