Teaching anecdotes

In the early '90's, I taught a first-year, second-term course on elementary data structures. In the winter of 1993, I placed on the midterm a question that asked each student to write a function "occurrences" which counted the number of occurrences of a key value in a linked list of records. In the course of marking the midterm, I noticed that some students were spelling "occurrences" wrong in their answers. This is not an easy word to spell, but it was spelled correctly three times in the body of the question, and the only place students needed to use it in their answer was in the header of the function, which was written out in full in the statement of the question.

I asked the markers to keep track of the number of misspellings. Out of about 400 papers marked, roughly 50 had "occurrences" misspelled. I mentioned this to the class while discussing the midterm results, and told them there would be a question on the final exam asking for the correct spelling of "occurrences". This brought the expected laugh.

On the final exam, I placed a question that asked each student to write a function "occurrences" which counted the number of occurrences of a key value in a tree. Part (a) of this question read, in full, "What is the correct spelling of the word 'occurrences'?", for an easy and amusing two marks. Part (b), which asked for the code for the function, used "occurrences" in its text in the same fashion as the midterm question.

When we started marking, someone sang out, "Hey, this student spelled 'occurrences' wrong!". Then we had another, and another. Out of 364 papers marked, there were 142 wrong answers to part (a). There were a number of students who spelled "occurrences" differently in their answers to parts (a) and (b), but we did not keep statistics on this.


This course also had a lecture on the history of computer science. I always enjoyed giving this lecture, but many instructors skipped it, because they didn't care for the material and it could not be tested anyway. I put an essay question on the winter 1994 final exam. For five marks out of a hundred, students had to write a 100-word essay on one of three topics. One of the topics was "Discuss the contribution of Alan Turing to the field of computer science." Here are four of the essays, in full, with all original mistakes reproduced. (Mistakes in content, as opposed to spelling and grammar, can easily be detected with the help of Web sites giving brief biographies of Turing.)

Before World War II, Alan Turing created a simple computer consisting of 0's and 1's that would help solve polynomials. During WWII, at Bletchley Park, he wast the first person to break the code of cryptography using an algorithm he formulated. His most important contribution to the field of computer science was the creation of a computer that could tell in the next room if it was a machine or a human. This research became the advent of artificial intelligence. With Alan Turing's contribution of AI, the research carried from there on.

In 1936, Alan Turing creates a computer language which called "Turing". After the Second World War, he created a Turing test for this computer language. This "Turing" language was the earliest computer language, and guards some authors to create some other computer language. For example, Basic, Pascal, Ada, etc. Actually: Alan Turing was the acestentor of all computer science. He brought the great concept to the field of computer science.

Born in 1912, Alan Turing is one of the major figure in computer science. Early in his life he worked on programmable machines. At age 24, he demonstrated his new invention, a 'computer' which took some types of tape as the main programming tool. The machine was going to different places on the tape whether or not a certain state was achieve. But one of his main proccupation was the artificial intelligence. In 1950 he wrote an algorithm which allows humans to see if a computer is intelligent. Touring died early, but his work still somehow actual even in this world where the changes in technology are so fast.

Alan Turing began his developments by building the first computational machine, based on BaBage's plans (Babage could not have accomplished his machine as he didn't have the precision machinery to build it.) This machine was the first to calculate functions and values. Alan throughout his carreer has been developing machine made calculating tools that will take some of the heavy burden of computations off the human shoulders. Alan in conjunction with the U.S military, tried to develop machines that will calculate projectiles or bombs and missiles, machines that will break codes, calculate flying pathes etc. Turing had a major role in algorithm development and proving its correctness. Turing ended his brilliant carreer by injecting poison into an apple and eating it as he was fed up with society's criticisms of his homosexuality (Note. and may that is why APPLE is called APPLE)