Overview of the Discipline of Computer Science - Guide to Teaching Computer Science: An Activity-Based Approach - page 48

complex) topics, the special attention they receive in the MTCS course can high-
light their importance.
We present several tasks that can be facilitated with respect to abstraction 14 . Clearly,
there is no need to facilitate all of them; each instructor should choose the activities
that fit his or her class and his or her pedagogical considerations.
Activity 19: Abstraction—Definition
Based on their familiarity with the concept of abstraction from their computer
science courses, students are asked to define the term “abstraction.” After
the definitions are collected and discussed, a short lecture is given that sum-
marizes the students' contributions and adds concluding remarks from the
computer science literature.
This activity can serve also as a good opportunity to discuss with the stu-
dents the role of definitions in learning processes. For example, one teaching
dilemma in this context would address the best timing to introduce a full and
formal definition.
Activity 20: Abstraction—Teaching Planning
Students are asked to design activities for the teaching of abstraction. The
working assumption behind this task is that when one teaches a certain con-
cept, especially a complex concept, such as a development heuristics for com-
puter programs, one deepens one's own understanding of that concept.
After working in teams on this task, the students present the activities to
their classmates. Indeed, as is intended, when students present the activities
they have designed, many issues related to the concept of abstraction are clar-
ified, elaborated on, and refined.
Activity 21: Abstraction—Pedagogy
Students are requested to explain why methodologies, such as abstraction, are
difficult to teach. In order to illustrate the pedagogical potential of this activ-
ity, we present some of the explanations presented in our classes by prospec-
tive computer science teachers:
• Inordertoteachabstraction,weneedconcreteexamples,andthuswelose
the generality inherent in the topic.
• Effectivediscussionanddemonstrationofthepowerofabstraction[…]
can be carried out only when based on complex problems. These complex
problems may distract our attention from the topic, and we should share
our mental resources between the problem itself and thinking about the
methodology (such as abstraction).
14 Based on Lapidot and Hazzan ( 2003 ).