2 APPROACH
Effectively capturing solution steps and strategies
requires a tool that is educationally justified. It must
follow sound pedagogic principles and contribute to
learning, and it should provide an environment that
freely allows creative problem solving without
increasing cognitive load. It should be possible to
capture solution steps without disturbing the user.
Multi-touch interaction is a new technique that
allows users to interact naturally with digital objects
in a physical way, and could help to address the
requirements. The pedagogic advantages of using
gestures have been studied (Drews & Hansen, 2007;
Goldin-Meadow & Beilock, 2010; Segal, 2011) .The
studies show that multi-touch technologies can
benefit cognition and learning (Barsalou,
Niedenthal, Barbey, & Ruppert, 2003), augment
working memory (Goldin-Meadow, 2009) . Also,
the mode of interaction allows for bimanual input
which increase the parallelism of manipulations and
reduce the time of task switching(Jiao, Deng, &
Wang, 2010).
Consider a two-stage arithmetic word problem
that involves three numbers, say 2+5+8. Students are
typically taught to solve the problems in two
separate stages i.e. by adding numbers in pairs.
Fischbein et al. (1985) argued that intuitive models
associate addition with putting together. The first
stage adds 2 and 5; using bimanual multi-touch
interaction makes it possible to simultaneously work
on the two numbers. Although it is possible to use
single touch to interact with the numbers one at a
time, it is rather cumbersome, less intuitive and
requires too many steps. The first step produces an
intermediate result which is used in the next stage.
It is interesting to note the first step has six possible
combinations (2+5, 2+8, 5+2, 5+8, 8+2, and 8+5)
and the second step similarly has six possible correct
combinations of the number pairs (7+8, 10+5, 7+8,
13+2, 5+10, and 2+13). The diversity of solution
paths increases if the other arithmetic operators (-, x,
÷) are required to solve the problems. Capturing the
particular number choices made by the student
during the interactions should provide detailed
feedback on the steps the student has taken to solve
the problem. This feedback provides an opportunity
to examine the strategies adopted in tackling the
problem.
To capture the solution steps without increasing
the cognitive load,(Chandler & Sweller, 1991) the
tool needs to implement a smooth user interface
which allows students to enter the solutions freely
and easily. The interface should present the question
and the solution work areas. For this study, the
problem text and the solution workspaces are placed
together on the same page. This aids the student
memory of the problem context and requirements.
This arrangement is known to have pedagogical
value and has been used in different studies (
Suraweera & Mitrovic 2002; Stone et al. 2009;
Batmaz et al. 2009) .Also, it allows the student to
focus fully and continuously on the task at hand
without having to flip back and forth between pages.
Another advantage is that it facilitates user
interactions between the workspaces with minimal
disruption. The solution space will not provide any
toolbox, options or hints and should allow free form
entry design space.
The method of capturing steps and strategies is
comparable in complexity to that used for design
rationale capture – an area widely studied. Design
rationale has been defined as the reasoning and
argument that leads to the final decision of how the
design intent is achieved (Sims, 1997). A variety of
methods have been used to capture the rationale,
each has its advantage and disadvantages. A method
known as reconstruction method captures the
rationale after the design. This approach does not
interrupt the flow of the design effort but does not
provide accurate or complete rationale capture,
because people usually do not accurately explain
how or why they do things. Another method referred
to in literature as apprentice system Sims 1997),
requires asking the designer questions as the design
action is carried out. This method is time consuming
and frequently interrupts the design effort. A third
approach captures the rationale implicitly. This
approach is used for this work as it does not obstruct
the process and has minimal time overheads.
2.1 The Multi-touch Arithmetic Tool
The prototype tool developed on the iPad is called
the multi-touch arithmetic tool (MAT). The tool
supports questions of different complexities
including all arithmetic operations and provides and
captures solution steps. Figure 1 presents a
description of the tool. It has word problem pane on
which questions are presented to the student and the
solution pane.
The word problem text section presents problems
with numeric values that can be dragged to the
solution area by using simple touch and drag
gestures with one or both hands. The numbers
dragged on the solution pane are referenced to the
numbers on the problem text using techniques
developed by Batmaz and Hinde (2006). The bottom
UseofMulti-touchGesturesforCapturingSolutionStepsinArithmeticWordProblems
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