Journal of Computer Assisted Learning (1996) 12,33-46
Designing interactive learning en vironmen ts Y. Akpinar and J. R. Hartley Computer Based Learning Unit, Leeds University
Abstract As computers become more prominent in classroom instruction their modes of use are extending, for example as surrogate teachers in tutoring or as curriculum enrichment in simulation applications where students are more investigative in their learning methods. However, within the classroom such programs often have effects and are used in ways that were not always anticipated by their designers. This argues for computer assisted learning (CAL) environments in which the software is interactive but is able to adapt to different styles of learning and teaching. This paper argues for and describes the design principles of such environments, taking as illustration an application in the fraction domain. Following its implementation, initial evaluation data taken from school-children showed marked performance improvements, and indicated how design features of the system (FRACTIONLAB) contributed to their understanding.
Keywmds: Computer assisted learning; Fraction domain; Interaction languages; Interactive learning environments.
The capabilities of the electronic computer have stimulated the design of a variety of instructional programs. Responding to behaviourist views of a feedback-controlled shaping of learning, tutorial packages have been developed and shown performance improvements particularly in achieving competence objectives through practice (e.g. Suppes et al., 1968). However in these types of programs the initiatives given to the student are limited. The material, tasks and feedback comments are pre-stored, and the user has to operate under the control of the program, answering questions or undertaking tasks within highly directed formats. Spontaneous questions or suggestions from the student, or other requests for remedial help are not permitted unless they have been specifically anticipated by the teacher author, since the program has no conceptual knowledge of the domain but operates under pre-stored prescriptions.
Accepted 9th May 1995
Comes ndence: J.R. Hartle Corn uter Based Learning Unit, Lee& Kversity, Leeds, LS?9JT, I& Email: firstname.lastname@example.org
34 Y. Akpinar & J.R. Hartley
These programs are, nevertheless, conceived as surrogate teachers able to be assimilated within the conventional organisation of the classroom. But they need careful preparation so that error and diagnostic feedback will be understood and related to the underpinning concepts of the domain. Limited resources may also encourage teachers to have pairs of students working together with the advantage of increasing peer interaction (Carney, 1986; Hawkins et al., 1982) and this can be an important influence on learning (Podmore, 1991). Hence the introduction of even such prescribed and directed programs can cause a shift towards greater learner and teacher involvement in instruction though the programs were not specifically designed to encourage this re-orientation.
So-called artificial intelligence techniques have led to the development of tutorial programs that contain domain knowledge in a form which allows them to generate task materials and answer types of students' questions (Anderson e f al., 1985; Anderson e f al., 1986; Burton & Brown, 1982; Brown, 1985). These systems can, therefore, give greater interactive support to students but they tend to be highly specialised and have been implemented as proof-of-concept rather than as institutional packages which are used in day-today teaching. Moreover, as Newman et al. (1989) point out, such systems though sophisticated, are far from taking adequate account of the social context of learning. Although relatively few evaluation studies of these types of programs in the context of classroom learning are in evidence, a two-year qualitative study of eight classrooms by Schofield et al. (1994) with Anderson's geometry tutor (Anderson, 1986) noted that rather than replacing teachers, the program became an additional enriching resource. Moreover, while recognising the greater skills of the human teacher, students very much welcomed the program since it placed the type and amount of support more clearly under the control of students, and to which the teacher could respond. But as Schofield e f al. noted "none of these changes were envisioned by the system's developers".
Similar comments can be made about other forms of computer assisted learning. Simulation programs are designed to encourage investigation as students form and test hypothesis about the underlying model. However this again requires careful preparation so that learners have an adequate conceptual framework on which to base and modify their hypotheses (Bork, 1987) and simulation programs are not usually designed to deliver this support. In the classroom, the programs are often used by small groups of students and there is evidence (Van Lehn, 1988) that these student interactions and explanations result in clear learning benefits. However the Conceptual Change in Science Project (Hartley et al., 1991) which used both simulation and qualitative modelling programs showed that unless such discourse reached the students' causal beliefs (in contrast to operational talk about the system and its displays) conceptual change could not guaranteed. A teacher is required to engineer such interchanges, but the designers had not given detailed consideration to these wider modes of use and classroom -upport, and the changing styles of teachinghearning that might ensue. To
fair, these consequences were illuminated by evaluation studies that
Designing interactive learning environments 35
focused not only on learning benefits but on the social context in which the learning took place.
A further example is that of LOGO (Papert 1980) which provides pupils with a computer language to reveal, exploit and extend their knowledge in a principled way, for example in Turtle geometry. A computational metaphor of variables, patterns, nested procedures and recursions acts as a framework for this development which links children's direct experience (e.g. in drawing shapes) to organised procedures expressed in the LOGO language. Papert's conception was that of individual learners building up their own 'libraries' of LOGO procedures that represented their extending knowledge. However in practice, and not entirely as a result of a shortage of computing resources, LOGO is seen as a collaborative activity for small groups of children, though the language was not designed from this viewpoint.
In summary we argue that computer assisted learning programs should be designed to take greater account of their possible and differing modes of use, and the varying requirements of direction, support and exploratory/investigatory methods that might be employed in the classroom. Hence the aim is to widen the design focus to develop what we consider to be interactive learning environments (ILEs). What is meant by the term and its functional components will be described briefly, and then illustrated by an example (FRACTIONLAB) taken from the fraction domain. Data from two initial validation studies with school children form a concluding discussion.
Interactive Learning Environments
ILEs should be designed to support a variety of teaching and learning styles, regulating the locus of control between student and system, and accommodating task-based methods that are feedback rich, illustrative mechanisms that support conceptual understanding, and learner-controlled investigations and problem solving. The functional components of such ILEs have been discussed in detail elsewhere (Akpinar, 1994) but in outline they consist of
an 'object world representing the domain, together with: a student-system interaction language by which learners can operate on the object-world in ways which show the effects of their actions (thus providing immediate feedback) and which link to representations of the object world and its relations at higher levels of abstraction.
Thus learning is envisaged not only as an improvement in performance but as a development of understanding at a more abstract and general level. Further components are:
a Lesson Office (Draper ef al., 1991) that is needed for specifying and managing the task curriculum, and providing student records; user-system interfaces which are required for students to apply the interaction language and manipulate the object-world, and for teachers to specify and customise types of curriculum tasks for the Lesson Office.
36 Y. Akpinar & J.R. Hartley
A more detailed architecture of an ILE is shown in Fig. 1 and it is clear that a domain representation (i.e. the conceptual and procedural knowledge summarising the cumculum) is a crucial prerequisite for the ILE design since it determines the 'objects' (concepts or procedures) their attributes and inter-relationships and hence the operations users can perform on them. This is shown in the 'Component Specification and Interaction' box in the Environment panel which also has an interface to allow the teacher/designer to set out this analysis of the domain. The representation language (i.e. the student-system interaction language) should, as noted above, enable students to operate on the object-world and, ideally, allow them to develop their procedural or explanatory models of the 'world' at higher levels of abstraction.
3 . 1 L
Interface iz I L
Screen Design F
v Interface Fig. 1. The architecture of LEs
Designing interactive learning environments 37
The domain representation also guides the curriculum of tasks to be specified by the teacher. These are placed in the Lesson Office, from which the Task Manager is able to display the appropriate task (selected in pre- determined sequence or adaptively by taking performance records into account) and manage the actual interactions with the learner. Typically a task specification includes instructions and/or material for the student, the domain objects and ILE facilities permitted to be used by the learner, and any additional feedback or concluding information that is to be displayed. The system-learner interface allows students to undertake the tasks (via the interaction 'language') and to see the consequences of their actions and decisions. Hence, via the Lesson Office task specifications, the teacher can follow a directed or an exploratory approach and also adjust the ILE for individual or small group working.
The FRACTIONLAB ILE
As proof of concept, and to test and illuminate the design principles, an ILE was designed for the fraction domain. This is a topic which, although its influence in the mathematics curriculum is declining, causes learning difficulties for school children (Hart, 1981; Behr et al., 1992) in understanding concepts (e.g. equivalent fractions) and symbolic notation, in manipulating fractions and in solving problems (see Kerslake, 1986; Harel, 1990; Ohlsson, 1991; Streefland, 1991; and Dugdale, 1992). Further it is a domain where types of instruction are likely to be varied and include exposition and illustration, procedural explanation and practice, and problem solving. Hence the ILE, following the principles and components noted above (namely the 'object world, the student-system interaction language, the Lesson Office and the user-system interface) should include the following features to support the approaches to learning and instruction:
interactive 'fraction' objects and operators that are visual and can be directly manipulated by pupils; mechanisms to check the validity of students' methods, and to provide feedback on the appropriateness of their actions in relation to the task; supporting links between the concrete and symbolic representations of fractions, with the ILE able to display these forms so that the equivalence (and meaning) between them is apparent; the system should also be able to move its presentation modes to the symbolic (e.g. through a 'fading' of pictorial or graphical representation) as students gain in competence; allow experimentation with concepts and procedures in ways that relate to the pupil's experience; thus supporting guided discovery as well as more directed methods of instruction; allow the learning to be contextualised and procedural via the types of task that are specified and managed through the Lesson Ofice.
Following discussions with teachers, who suggested fractions as a topic with which their students had difficulties, the fraction domain was represented as a semantic network showing the relations between fractions, their components, equivalent fractions, and procedures of addition, subtraction,
38 Y. Akpinar & J.R. Hartley
multiplication and division of fractions. A fraction was conceived as a manipulable object (an equal division of a whole, or equivalently as a ratio) which could be segmented, measured, combined with other fractions, and represented in pictorial and symbolic forms.
Hence the metaphor of a FRACTIONLAB was developed with the learner being able to directly manipulate 'fractions' and 'wholes' through a set of operators that include a Segmenter, Measurers, Sticker, Copiet., Adder and Subtracter. The working of these operators was under student control with each phase of the procedure shown visually, and linking to a symbolic representation. For example the Segmenter takes as input a circle, visually displays an 'equal partitioning' under instruction from the user, and generates a fraction placing it in a box and showing the graphical form of the fraction with the symbolic form available by pointing the mouse at the fraction object. The Segmenter can also rotate the fraction segment, but its main feature is that it links the operational stages to the symbolic representation. For example, Segmenter can have a whole circle object (1 as the numerator) dropped into it, which is divided into segments (e.g. 8 the denominator) producing (1/8). Thus all the symbols have an operational meaning related to the stages of processing and using the operator sequence as a 'language' which links the pictorial and symbolic representations.
A further requirement is for an operator (Measurer) that enables students to 'measure' fractions (shown in Fig. 2 as shaded segments of a circle). Students might also wish to compare or order fractions, to test their equivalence or to consider the various equivalent values that can label the same fraction. For those objectives FRACTIONLAB is able to provide more than one Measurer for pupils to use simultaneously. Similar to the Segmenter, the Measurds ) was designed to have three display units corresponding to the phases of measurement. The input is a fraction segment, which is placed in a measuring 'circle' on being given the...