The Web and Model-Centered Instruction
Andrew S. Gibbons
Kimberly Lawless
Utah State University
Thor A. Anderson
Netscape
Joel Duffin
Utah State University
Information and Instruction
Both economy and effectiveness will determine the future success of the Web as
an instructional distribution channel. The instruction the commercial web delivers will
have to be powerful, but it will also have to be affordable. Consider the effectiveness
issue. The web is today without dispute the world’s premier information system. But
what will it take to make it the premier instructional system? That answer has to take into
account the difference between instructing and informing. For our present purposes, we
will define instruction as the engagement of two or more individuals’ wills or plans in a
cooperative effort to first establish and then verify new personal meaning and
performance capacity.
Verification—the search for evidence that learning goals have been attained—
distinguishes instructing from just informing. You are never tested to see if you learned
what the newspaper informed you about, but you must demonstrate performance ability
and the attainment of certain knowledge before you can be certified in an area of
professional practice. During instruction, two individual wills negotiate learning and
performance goals and then work in concert to achieve them. Sometimes the goals are
unspoken and sometimes they are explicit, but they always exist, if it is instruction.
What makes instruction effective? That question has been the center of a great
debate, and some useful new answers are emerging. One thing certain is that instructional
techniques that have been used regularly for years are being joined by new ones. Perhaps
a better way to put it is that instructional methods that have been given low priority in the
past are now being rediscovered and given much higher priority: at the same time, some
of the old standbys are being given lower priority. The standard forms of the past 30
years are only a small subset of the possibilities that can be generated by considering new
instructional roles, activities, formats, and relationships made possible by these newlyemphasized methods.
Recent developments to remove some of the old assumptions of instruction
emphasize the importance of the social context of learning (Collins, Brown & Newman,
1987; Rogoff, 1990), learning by problem solving (Barrows, 1985, 1992), and the
situation of learning in realistic contexts (Lave & Wenger, 1991). These trends are
closely related to an evolving instructional viewpoint called model-centered instruction
(Gibbons, 1998; Gibbons & Fairweather, 1998; Gibbons & Anderson, 1994).
Model-centered instruction, which is described later, involves an instructional
relationship consisting of a learner and a companion-in-learning who together observe
and interact with one or more real or modeled environments, cause-effect systems, and/or
samples of expert behavior. The companion supplies instructional support in a variety of
forms and through a variety of roles as the learner solves a series of problems of
escalating difficulty defined with respect to a set of models or systems of escalating
complexity. The work of White and Frederiksen (1990) summarizes principles for
defining externalized instructional models, from which learners can construct
corresponding internalized mental models. The import of model-centering is that it
assumes experiencing a model or a system in some form as a primary instructional
means. Model-centering assumes also that a secondary, companion function accompanies
that experience in ways that guide and support learning.
How can the Web make the transition from offering almost exclusively
informational services to accommodating a greater share of truly instructional ones? This
will entail considerable change: (1) a new web designer mindset changed from traditional
instructional views to ones that incorporate model-centering, and (2) tools of new kinds
not widely used yet, even for the development of stand-alone (non-web-based) computerbased instruction. As new instructional viewpoints such as model-centered instruction
emerge to bring out the unique strengths of the computer as an instructional tool, they
will broaden the computer’s traditional role to include new uses as a multi-purpose tool
(Lajoie & Derry, 1993).
To tease out the implications of the instructional web, let’s look at computerbased instruction in terms of its internal structures.
Instructional Considerations: Convergence of Instructional and Logical Constructs
An instructional designer, through the act of designing, builds abstract event
structures that embody strategic plans. An event structure may consist of a presentation of
information, a quiz, a practice exercise, a problem to solve, a demonstration of
performance, or one of numerous other options. The designer designs these event
structures so that a learner can have goal-relevant experiences. In order to move from
design to product, designers must match these event structures with the expressive and
interactive structures supplied by—and unique to—the medium they are using for
instruction. Books supply page structures; computer-based authoring tools supply
programming structures like control or decision points, icons or frames, branching,
graphic objects, and text objects.
The most important issue for computer-based instruction of all kinds—including
web-based instruction—is the convergence zone shown in Figure 1. This is the place
where the designer’s abstract instructional constructs and the concrete logic constructs
supplied by the development tool come together to produce an actual product. At this
point, the abstract event constructs are given expression—if possible—by the constructs
supplied by the development tool.
This zone is especially critical for computer-based instruction because CBI
demands explicit and detailed specification of logical structures to a degree required by
no other medium. Other media depend heavily on pre-sequenced blocks of content,
message, and representation. The computer is capable of computing a sequence of events
for individual learners.
Attention to the convergence zone by CBI designers is crucial because the zone
moderates: (1) the exactness with which the designer’s strategic plans are implemented
and (2) the time and effort required for developing the instruction. The convergence zone
is where the effectiveness and the cost of the instruction are mostly determined.
Figure 1 shows that computer logic constructs are supplied by specific
development tools and tool families. For instance, a frame-based tool supplies different
types of frame (subroutine) logic. An object tool supplies generic objects that can be
customized by the user to perform specific functions.
Here is what happens at the convergence zone. The theoretic or paradigmatic
orientation of the individual designer causes certain kinds of instructional construct to
appear in his or her designs. The development tool chosen determines the logic constructs
that will be available for use. The match or mismatch between the designer’s instructional
abstractions and the tool’s logic structures at this point either constrains or supports the
degree of implementation of the design. Since even software tools are maximized for
certain uses and minimized for others, it is almost unavoidable that a given development
tool will either express or restrict a given instructional event plan. This phenomenon has
led in the past to a restriction in the designs themselves and encourages a kind of
conformity to the tool rather than an expression of more powerful and effective designs.
This pattern from the past needs to be reversed, and the instructional Web may be an
opportunity to do so.
Instructional
Paradigm
Development
Tool
Instructional
Constructs
Tool Logic
Constructs
Zone of
Convergence
Figure 1. Factors that define a convergence zone where abstract instructional constructs
and logic tool constructs meet in computer-based and web-based instruction.
In terms of abstract design constructs, the Web’s current metaphor is the network
of hyperlinked documents and resources. Web tools provide logic constructs that match
this metaphor perfectly. With a web tool you can construct web pages (of the document)
with special formats provided by HTML. Pages are populated with various textual and
graphic information resources and can provide special effects and interactivity using
applets and controls, which are simply types of resources. Links or hotwords are the paths
that tie pages together.
The design constructs used for web pages for the most part correspond directly
with the tool constructs provided by web development tools, and if the informational
metaphor of the Web was also a suitable instructional metaphor, then the transition to the
instructional Web using existing tools would be smooth and uneventful. But informing is
not instructing, and so a significant shift toward instructional development tools for the
web can be expected, and that may pose some difficulties to the mindset of designers and
to the formation of development tools. The shift will involve not just web page
construction tools but the information-linking design constructs now firmly implanted in
the minds of tens of thousands of Web designers. These patterns of thinking and
designing may in the short term hinder the use of the Web for highly interactive
instruction, because they conflict with the instructional constructs that must come to
share the Web. Let’s examine two prevailing views of instruction in more detail and the
tool requirements they entail.
Two Instructional Paradigms
Hannafin and his associates (Hannafin, Hannafin, Land, & Oliver, 1997) provide
an excellent description of two major views of instruction in their discussion of
instructivist versus constructivist instructional approaches as foundations for instructional
designs. These two major views of instruction lead a designer to apply much different
abstract instructional constructs in their designs. The task of expressing these two
families of constructs in the form of computer logic brings the designer face to face with
two different families of logic structures.
Gibbons and Fairweather (1998), for instance, define multiple, nested levels of
construct that are involved in direct, or tutorial, instructional designs (see especially pp.
171-180 and 421-462). They define four levels of design construct: a strategic level, a
content level, a message level, and a representation level.
At each of these four successive levels, abstract design constructs from the
previous level unfold to create a complete and detailed design, whose structures at the
lowest level must in some way be made to correspond with the logic structures supplied
by some authoring tool. This is the convergence zone. (Keep in mind that for the present
moment we are focusing on direct, tutorial, strategy-centered instruction. What we are
saying does not apply to the second type of instruction defined by Hannafin, which we
will treat in a moment.)
At the highest level of design construct (the strategic), the structure consists of a
strategic plan divided into functional sub-constructs (for instance, “present information,”
“provide an appropriate demonstration,” “provide practice”). Each of these strategic subconstructs splits along the lines of content structure to produce smaller constructs
(“present one example of a concept class” or “practice of one step of a procedure”).
These content-tempered sub-constructs break down further to produce message subconstructs (“present the definition of the concept,” “present one example,” “present one
paired non-example”). Message-tempered constructs unfold one more step to produce
representational sub-constructs (“provide the text portion of the definition at the
appropriate screen position and at the right timing,” “accept the learner’s response to the
non-example and check it”). It is at this lowest level of detail, the representational, that
the structures, which to this point have been only conceptual and involve an abstract
design, are made to correspond with the reality of some set of logic structures supplied by
an authoring tool.
Displaying the text for the concept definition may involve presenting a text string,
a bitmap, or a fixed string in some typeface at some size, and at a particular place on the
display. Accepting the learner’s response involves specifying several items of
information: location of the response, type of response, disposition of the response
(stored or not stored), appearance of the response on the display, and so forth. The
authoring tool may or may not provide the type of service the author envisions. If it
provides it, it may be easy (inexpensive, modest skill) or hard (expensive, high skill) to
arrange. At this convergence zone and in this way, the authoring tool influences the cost
and effectiveness of designs.
Hannafin and his associates identify a second type of indirect instruction that
relies more heavily on direct experience supplemented by coaching and other forms of
learning augmentation activity. The constructs required to create this type of instructional
experience differ considerably from those for direct instruction. They include:
environments in which a problem can be posed and solved; the data and representations
related to the problems themselves; interactive cause-effect systems (computer models)
that can be manipulated during problem solving; systems of expert behavior that can
supply models of performance for learners to observe; resources that supply content for
problem solving; dramatic overlays that situate problems in realistic contexts; recording
and analysis tools for the collection and manipulation of data; communication tools; and
auxiliary instructional features that supply the functionality of a learning companion.
These abstract design constructs can be subdivided and eventually matched with
the logic constructs of the tool that will give them life, just like direct instruction
constructs, but the indirect design constructs break down in different ways. For instance,
environments for problem solving normally divide into individual locations (real or
metaphorical) that can be “visited” to obtain information that is available there; pathways
connect these locations, implying the need for movement controls. The representations
used to display locations and their information ranges from simple textual presentation at
one end of the spectrum to virtual experiences at the other, and the range of options
between these extremes includes every form of representation available to computers and
all combinations of them.
The other high-level constructs listed earlier for indirect instruction break in
similar fashion into sub-constructs in their own ways, but the goal of the reduction
process is the same, whatever the structure, and whether for direct or indirect instruction:
to produce a set of abstract design structures that can be matched with the logic structures
offered by the development tool of choice. Since the constructs for indirect instruction
differ from those of direct instruction, it turns out in many cases that the logic structures
supplied by authoring tools designed primarily for direct forms of instruction match
poorly with the abstractions created for indirect forms of instruction. This will prove to
be the greatest challenge for the instructional Web.
Tool Implications
The benefit obtained from specialized web authoring tools is not just functionality
but productive functionality. Increased productivity is the primary reason for building
such tools. If no authoring tools existed, the designer would be required to use a highlevel programming language like “C.”
In fact, some organizations do use high-level languages despite their higher
development price tag because they have had a chance (paid for by volume production) to
design their own set of specialized routines (logic structures) that can be strung together
according to need to match a set of standardized design constructs. In effect, they have
constructed their own special purpose authoring tool. Many large training software
vendors are positioning themselves and their products to be web-compatible in this way.
Likewise, virtually all major commercial authoring tool vendors, seeing the potential (can
we say inevitability?) of the Web as an instructional channel, are migrating their products
toward web compatibility and web-friendliness. Instructional designers now face difficult
tool choices and wonder if there is a best choice that will not require future adjustments
and re-programming of their products. Even more important, many are wondering how
they will be able to implement a newer instructional paradigm (indirect instruction) in a
medium that is not yet fully compatible (in terms of productivity) with the high
interactive demands of the old paradigm (direct instruction).
Examining the Web’s Underlying Metaphor More Closely
During the coming period of transition, where the Web will try to embrace
interactive instruction in addition to information access, it is a good time to reconsider the
basic structural metaphors of instruction and to compare them with the structural
metaphor of the Web and its tools. We should ask, “Can we see a clear path for the
creation of Web development tools that will implement today’s instructional metaphors
and allow for their future growth in feature and function?”
We believe that the answer to this question begins with a closer inspection of the
language metaphors currently available for Web development. We should begin an
inquiry by examining the basis of the most common, popular, user-friendly, and
productive web language, HTML, to see if it supplies the necessary logic constructs to
implement the kinds of direct and indirect instructional designs we have described.
HTML is the lingua franca of the web for the average designer. It is the tool most
friendly to the average web page designer, and it is the tool taught to most beginning
designers. It is designed specifically to allow page authors to prepare documents
containing a range of resources and linkages once for interpretation and display on many
properly configured computers. It allows designers to ignore differences in computer
hardware, operating systems, display size, and local software preference settings.
This alone is a spectacular achievement, especially appreciated by those who have
worked in earlier environments where cross-platform compatibility was in most cases
unobtainable. But much of HTML’s compatibility is a result of its membership in a larger
group of markup languages (ML), all of which have similar cross-platform
compatibilities. These markup languages are all descendants of a parent language called
SGML (Standard Generalized Markup Language). Each markup language in the SGML
family has the capacity for communicating a specific type of document, with its
formatting, to a distant browser.
The important point to be made is that markup languages derived from SGML are
all based on the document metaphor, with a document, somewhat like a data base, having
a certain standard structure (Leventhal, Lewis, & Fuchs, 1998). A markup language is
simply a way of tagging the individual elements of a particular type of document (having
a specific internal document structure) before sending the document’s elements for
display.
HTML documents have display elements such as “body,” “title,” and “list.” They
also have reader-reactive elements such as form fields, click-sensitive graphic areas, and
buttons. They also have relational links that permit the elements of the document to be
accessed in various orders. But the range of structures and interactivity using this set of
elements and resource types—as impressive as they are—is limited, especially when the
processing of a learner response is taken into account. Moreover, markup languages are
not sensitive to the context or meaning of a reader’s response, so a programmer has to
supply it in the form of answer processing logic, which is not within the range of HTML
user-friendliness. To handle these additional requirements, new tools like Java, and Perl
are called into use and interfaced with HTML, and the user-friendliness and productivity
of web authoring plummets.
To escape some of the limitations of HTML, groups of users with specialized
document types have created their own markup languages—derived from SGML and
usually created in a tool language called XML—for the authoring, transmission, and
display of documents that contain specialized structures. Mathematicians have
constructed a Mathematical Markup Language (MathML). Its structures include
formatting tags that allow the mathematician to specify to a browser how the individual
elements are linked in terms of meaning (semantic or content tags) and how they are to be
displayed.
A sample of MathML is provided by Ion and Miner on their web page,
Mathematical Markup Language: W3C Proposed Recommendation (www.w3.org/TR/PRmath/). The expression “x+a/b” can be tagged as:
<mrow>
<mi> x </mi>
<mo> + </mo>
<mrow>
<mi> a </mi>
<mo> / </mo>
<mi> b </mi>
</mrow>
</mrow>
The benefit of MathML is that equations that would otherwise be difficult to
display in readable form come to the reader looking just like equations on a printed page,
with spacing and placement of symbols just as they were intended by the author,
regardless of the computer they are displayed on.
Musicians have a Music Markup Language (MML). The benefits of Music ML
are the same: musicians can send otherwise unreadable musical documents in a form that
allows the receiver to read and interact with them.
These and other markup languages, however, skirt the issue addressed in this
chapter and do not deal with the implementation of highly interactive and sometimes
adaptive instruction over the Web. The central question we must ask is whether the
document metaphor and its implied logic constructs that lies at the base of the markup
languages can be used as the base also for implementing the conceptual structures we
have described—for both the direct and indirect instructional paradigms. We do not
believe that the document metaphor alone can suffice, unless the definition of
“document” as a data base of retrievable resources changes. The specialized markup
languages are designed for the display of static document content. In contrast, the content
of instruction, especially for indirect instruction which relies heavily on learner
interaction with models and expert systems capable of making instructional decisions and
exhibiting dynamic performance, is not easily contained within the boundaries of a
collection of static, categorized structures that store and fit neatly within a data base.
Indirect instruction often requires the construction of displays based on computed
responses to learner actions.
Tool Solutions
How can tools be made easier to use, even when the forms of instruction created
seem to be demanding more sophisticated logical structures and interactions between
independent logical agents? What patterns of tool use and siting of logic processing will
minimize traffic over the instructional web yet permit power, speed, flexibility, and
individual learner attention in products?
Some solutions present themselves that are within the immediate grasp of the
designer while longer-term solutions continue to evolve: (1) the construction of reusable
logic templates for direct instruction, (2) the construction of reusable components for
indirect instruction, and (3) migration toward tools with more flexible and broadly
applicable logic constructs for both types of instruction.
Reusable templates for direct instruction. For many years, computer-based
instruction developers have relied on template logic structures made of frames or handmade logic routines as an economy measure. Financial success for most CBI product
companies is possible only by adopting a template approach. The economics of the Web
will demand the same thing. Low-cost development will continue to be a requisite.
Reusable templates are the most direct way to this goal for some types of instruction,
especially the direct type.
Reusable components for indirect instruction. Indirect instruction logics employ
components that permit free play within an environment as well as system models and
tools for use within a problem solving environment. Just as templates can be used to
capture direct instruction logic for message delivery and practice interaction, reusable
components can be manufactured that create environments, simulate cause-effect systems
(models), and perform expert system functionalities. Many of these components can be
created as empty logic shells that are provided with usable data at the time of use.
Template components of this type have been used to create instruction for the
training of aviators (Gibbons & Rogers, 1991a, 1991b; Gibbons, 1993), and for the
training of library skills (Lacy & Gibbons, 1994; Wolcott, Gibbons, Lacy, & Sharp,
1994). These applications involve free-play environmental simulations followed by
intelligent, real-time, performance-referenced feedback.
These products involve the creation of independent, reusable components: a shell
simulation engine, and a separate shell expert system for feedback. These efficient and
compact instructional components are capable of generating instructional messaging from
problem data files and live response records of the learner. Duffin and Gibbons (1997)
and others (Gibbons, Duffin, Robertson, & Thompson, 1997) have also reported using
object systems to create simple, parameterized, and switch-controllable expert systems
capable of both coaching and feedback in either delayed or instantaneous mode. These
expert systems operate on selectable comparison sources—either the expert’s or the
learner’s own performance. These designs are well-suited to the web because of their
parsimony.
Migration to more flexible tools. Many designers find object-oriented
development systems more economical and more flexible for building structures typical
of indirect instruction. Not only can one-of-a-kind object suites be created, but templated
object structures have been used to create efficient but instructionally effective object
families (Gibbons & Thompson, 1997). Traditional authoring tool frames themselves can
be created using object tools, suggesting that object systems represent a superset of tool
constructs. In terms of web-focused object tools, Java appears to be preeminent, and
authoring interfaces are emerging that provide non-programmers access to Java
functionality. These facilitate designer creation both direct and indirect instructional
products and allow a larger number of authors to access the power of the programming
language.
Object tools are uniquely suited for the construction of models of both natural and
manufactured systems. The object-oriented approach to programming has its roots in
creating simulations (Shasha & Lazere, 1995). However, simulation models alone do not
constitute an instructional product. The experience of the model through problem solving
normally requires support in the form of instructional augmentations (coaching, hinting,
directing, explaining, giving feedback, etc.) that support the learner’s extraction of
information from experience, construction of knowledge, and formation of performance
patterns. These instructional augmentations often imply that two programs need to run
simultaneously or in close coordination. The independence of these functionalities is
essential for their portability and reuse.
Conclusion
We have tried to outline issues at the heart of web-based instructional design and
production. We have invoked one old and one recent instructional paradigm to show the
instructional implications for a medium hitherto purposed for information exchange. If
the Web is to supply both direct and indirect instructional forms, new tools for web-based
design and production must evolve.
Several decades of experience that have already accumulated in computer-based
instruction have shown that when the instructional constructs of a design correspond well
with tool constructs provided by a specific tool being used, and when reusable logic
patterns can be constructed and applied, the result is a product whose instructional plan is
preserved intact and whose cost is reduced. However, when there is a mismatch between
instructional and tool constructs, or when template logic cannot be used, instructional
designs are compromised, or costs soar, and there are less frequently exportable and
reusable elements of program code produced.
The task of creating economical development tools that implement a new
metaphor will be an especially difficult but critical challenge. Throughout the history of
computer-based instruction, there has been a tendency for logic tool constructs to initially
facilitate but later restrict the implementation of the designer’s strategic ideas due to the
relatively rapid advance of theoretic ideas compared with the relatively slow advance of
tools. Currently, conventional computer-based instruction faces these same challenges.
The advent of the instructional Web will accelerate progress—hopefully in both webbased and stand-alone CBI. We therefore look forward with anticipation to the creation of
the truly instructional web and more powerful CBI development tools than ever before.
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