To show that algorithm design is difficult, have students write algorithms, exchange their work, and then attempt to execute each others instructions.

  • For instance, have half the class write instructions for making a PB&J sandwich, while the other half does the same for making a paper airplane. Have them carry out those instructions without any input from the designers of the algorithm.
  • Make certain the message that computers can only do what they’re told is clear to the students.
  • Extra Information from CS Teaching Tips: For more information on the peanut butter task check out our tip from Janet Davis’s Paper on the activity.
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Tips from Frances P. Trees' section “Sample Syllabus.” in Deborah Power Carter’s The College Board’s AP Computer Science Teacher’s Guide.