Learners’ Alternative Conceptions - Guide to Teaching Computer Science: An Activity-Based Approach - page 95

An example of such a diagnostic exercise is included in Activity 44, presented
below (Sect. 6.3). If time allows in the MTCS course, it is recommended to ask the
students to prepare a similar set of exercises for other computer science topics. A
related idea is addressed in Activity 28 (see Sect. 4.3).
Errors and Improving Understanding : The mere existence of mistakes should be
acknowledged both in the computer science class and in the MTCS course. This can
be done by showing learners' common errors and discussing them, talking about
errors that learners exhibited in written tests, and most important, encouraging
learners to conceive errors as unavoidable positive phenomena that comprise an
opportunity to learn new ideas and improve current understanding. In some cases,
it is recommended to present a common error (known from the computer science
education research literature), even if none of the learners in the specific class did
not suggest it, and to discuss it with the learners.
In many cases, teachers are exposed to learners' alternative conceptions through
learners' wrong answers in written tests. In such cases, obviously, pupils describe
neither their (alternative) conception as part of their wrong answer nor the way of
thinking that led them to present the wrong answer. Therefore, the teacher should
“get into” the pupil's head, recognize the concept or topic that the learner does not
understand, try to imagine the pupil's conception of the said concept, and guess the
pupil's intention in the (wrong) answer.
Activities 44, 45, and 46, to be facilitated in the MTCS course, practice this skill.
Activity 44 is based on computer science education research (see also Chap. 4).
Activities 45 and 46 focus on genuine answers given by pupils in a test and the
alternative conceptions they expose: Activity 45 is based on the actual data taken
from a written exam; Activity 46 examines a short interview conducted with a pupil
who exhibited an alternative conception.
Activity 44: Exploration of a Computer Science Education Research Work on
Learners' Understanding of Basic Computer Science Topics
As mentioned in Chap. 4, knowledge gained from computer science educa-
tion research can enrich teachers' perspective with respect to pupils' difficul-
ties, misconceptions, alternative conceptions, and different cognitive abilities
and skills.
The general target of this activity is to present an example of a research
work to the students that deals with learners' understanding of variables—one
of the basic computer science concepts—including input, output, and assign-
ments, and specifically, to focus on alternative conceptions, mistakes, and
misconceptions related to variables.
The expected outcome of this activity is that in later stages, in the various
assignments that the students will work on, they will exhibit a wide perspec-
tive on learners' mistakes. In other words, it is expected that in future activi-