The Cryptic Crossword Puzzle as a Useful Analogue in Teaching Programming Simon School of Design, Communication, and Information Technology University of Newcastle PO Box 127, Ourimbah 2258, New South Wales [email protected] Abstract while another wrote “I don’t buy the premise” (Anon2 2003). Contrary to the apparent beliefs of many students, Nevertheless, the papers cited above, along with a wealth computer programming and problem solving are not of others, show that many reputable educators share the amenable to purely book learning. These skills can be perception that more students than expected have acquired only by practice, and even then, students with an significant trouble with programming courses. Unless aptitude for programming will acquire the skills far more faulty delivery is endemic among teachers of readily than those without. Unfortunately, aptitude is a programming, the existence of a relevant aptitude is concept that many students have difficulty appreciating. appealing as a partial explanation. This paper describes a novel approach to helping students understand the concept.. This paper is written in the assumption that there is such a Keywords: computer aptitude, cryptic crossword. thing as programming aptitude. However, as one of the aforementioned referees pointed out, the paper’s subject 1 Does computer aptitude exist? matter has potential pedagogical value even for academics who do not accept the existence of aptitude Many in the computing education community agree that (Anon2). there are students who take to programming and problem solving and students who don’t. They further agree that 2 The scope of this paper these skills are so important that students who don’t take to them tend not succeed in the course. Many papers have been written about ways of assessing the aptitude for programming and problem solving, from This phenomenon can therefore lead to high rates of explicit tests (for example, Tukiainen 2002) to implicit dropout and failure, which have sparked much soul- indicators such as a certain level of attainment in searching and many papers. “Disturbingly high failure mathematics (for example, Brown 1996). rates have been observed in first year Information Technology units at [Queensland University of But regardless of whether an assessment of aptitude is Technology] over the past several years.” (Brown 1996). made, and regardless of the nature of the assessment if A study at Monash University was “aimed at tackling one is made, there remains the problem of persuading the perceived problems in the teaching and learning of first less apt students that they will have great difficulty with year programming. The main concerns were high failure the course; that much as they might like computers, they rates . .” (Carbone 2000). A paper from the University are unlikely ever to attain a comfortable grasp of of Technology Sydney observed that “in many Australian programming, and might be well advised to realign their universities, the failure rates for first year programming study in a direction that can derive more benefit from subjects are among the worst across the university. Many rigorous study. students become disenchanted, and either drop out or This paper describes a simple analogue that can be shown resort to plagiarism.” (Lister 2000). to students to illustrate the nature of aptitude in a way that It must be acknowledged that this perception and most of them seem to grasp in one brief lesson. conclusion are by no means universally accepted. One The paper does not describe a study or a research project. referee of the draft of this paper acknowledged “a bias It simply describes, in the spirit of sharing useful ideas towards the proposition that the core problem addressed with one’s colleagues, an analogue that has been used in this paper is due to a faulty delivery on educators’ part with some apparent success. rather than a lack of aptitude in students” (Anon1 2003) Through the paper, the word ‘problem-solving’ will often be used to avoid repetition of the more cumbersome ‘problem-solving and programming’. Many good programmers would simply use the word ‘programming’ .Copyright © 2004, Australian Computer Society, Inc. This paper appeared at the Sixth Australasian Computing Education for this purpose, because they automatically problem- Conference (ACE2004), Dunedin. Conferences in Research and solve as they program. Practice in Information Technology, Vol. 30. Raymond Lister However, part of the problem with students who lack the and Alison Young, Eds. Reproduction for academic, not-for aptitude is that while they might eventually acquire the profit purposes permitted provided this text is included. syntactic and semantic knowledge to become reasonable puzzle is finished, many of the students are starting to coders, they often fall short in the algorithm development look enlightened, to feel that they now know how to solve that many good programmers do without thinking. The cryptic crossword puzzles. choice of ‘problem-solving’ is intended to emphasise this Next I give the students a photocopy of a different puzzle. aspect of the problem-solving and programming aptitude. Some are quite surprised to find that they can’t solve a single clue. 3 Explaining the notion of aptitude to students Now the parallel has to be drawn with problem-solving Many of my students, and I am not alone in this, have and programming; otherwise students will go away intriguingly little aptitude for problem-solving and thinking they have been shown that they can’t solve programming. They like computers, and are more than cryptic crossword puzzles. capable in some areas of computer use such as, say, Web page creation; but when it comes to solving a relatively Once it sinks in that being able to understand does not simple problem and implementing the solution in a necessarily imply being able to do, I go on to draw some programming language, they flounder. parallels between the cryptic crossword puzzle on one hand and problem-solving and programming on the other. If only these students recognised that they were floundering, and made a reasonably quick decision to 5 Lessons from the puzzle shift their attention to an area in which they were more capable, all would be well. But most of them seem to feel that because they qualified to enter the course, they must 5.1 Learning by seeing doesn’t work therefore be capable of completing it. In one particularly I started using cryptic crossword puzzles in this way troubling case, I saw a student devote nine years of his many years ago, in another discipline, simply to illustrate life to undergraduate study before finally being thrown the point that reading and understanding another person’s out by the university for his continued inability to deal solution to a problem does not in itself enable people to with the final-year courses. write their own solutions to similar problems. In a first attempt to let students know that there is such a Even if the techniques used are painstakingly explained, thing as an aptitude, and that not everyone who wants to that is not sufficient to teach students to use the program computers will be able to, I talk to them briefly techniques for themselves. about music and art. Having already seen this illustrated, students have no With regard to musical or artistic talent, students readily trouble believing it. As the course proceeds, a gentle accept that: reminder now and then can start to persuade students who • many people don’t have it; really do seem to be trying to learn to program just by • some of those who would like to have it don’t, and reading other people’s programs. end up either doing something else or scraping by in music or art; 5.2 Learning requires much practice • it has no correlation with academic ability; No matter how familiar one becomes with the techniques • there is no shame in not having it. of cryptic crossword puzzle solving, one does not become a solver without a vast amount of practice. On the way, it However, students see music and art as somehow can be very helpful to discuss the problems with a mentor different from everyday activities, while they see IT as or a fellow learner; but in the end, long-term dedicated very much an everyday activity. They are conscious of practice is indispensable to acquisition of the skill. the creativity required for music and art, while failing to see that problem-solving and programming might require Even with this practice, as some of the following points creativity of their own. They feel that everyone who will illustrate, the skill will only be truly acquired by wants to do music or art has the aptitude, and that somebody who has the aptitude. likewise everyone who wants to do IT will have the This is often the most difficult parallel for students to aptitude. Even among students who have studied IT for accept. Although they have just seen a counterexample, some time, the feeling persists that anything in IT can be their limited recollections insist that virtually any learnt with enough study. academic subject matter can be learnt by reading enough What was required, therefore, was a simple example of an about it. Yet the parallel with problem-solving and everyday activity, not generally thought of as creative, programming is a good one. that could be explained to students in a single lesson, and For example, the skill of debugging is seldom seriously that would have a high chance of persuading them that addressed in textbooks. There has been work on systems aptitudes are not just for music and art. that will help students understand compilation error messages (Kummerfeld 2003), but in the end, this 4 The cryptic crossword puzzle understanding comes only with long exposure, which in At the start of a tutorial, early in the course, I display an turn implies a great deal of practice.