Redundant content across SCOs
To maximize reusability, each SCO must be able to stand alone. As a result, much material that is secondary to the primary concept or process, but which is critical to the user’s understanding, must be included in more than one SCO.
An example from the project course would be the secondary issue of personal safety equipment. For this particular project, two separate SCOs, one on metal casting, one on furnace operation, both require the same basic information on personal safety clothing. In a traditional textbook or classroom setting, this material could be covered once and then referenced, when relevant, in later sections. Since an SCO cannot reference material covered in another SCO, this information must be offered twice. (See Figure 7.) To offer the safety equipment component as a separate SCO would require external reference from the metals and foundry practices SCOs and is therefore not an option. Since the proper safety equipment is so fundamental to the safe operation of the furnace, it would not be acceptable to leave out this information.
FIGURE 7 The safety equipment sub-SCO must appear in more than one SCO.
In addition to several totally redundant components, I ran into a whole range of semi-redundancies that also arise from the same construction and usage rules. Most of these might not be encountered in a different type of course structure, but by the same token I imagine that I have just scratched the surface of the possible topical relationships. In Figure 8, I have shown (in abbreviated form) three of the eleven chapter-level SCOs, one each on furnace operation, investment molds making and usage, and metal casting. For example, the SCO on metal casting, in order to be reasonably complete, needs to address the types of molds used to cast molten metal. Since investment molds are a common small-foundry technique the basic principles and practices of making and using investment molds must be covered, along with those for greensand molds, bonded sand molds, and the machined steel molds sometimes used in aluminum casting. This material on investment molds meets the basic needs of the reusable metal casting SCO but for this course, where students are expected to understand the deeper complexities of investment molding, this lower level instruction is not enough. When building one SCO that covers the deeper points of this molding process, and a metal casting SCO that covers only the high points, I have built a pair of SCOs that have some serious overlap. Yet both are necessary for my purposes, which include both building course resources and building serious reusability into all of my components.
FIGURE 8 Handling redundant objects in SCOs
In the short run these rules of design seem unnecessarily cumbersome, but I routinely utilize textbooks written by other people and I utilize videos, films and web resources to make or enhance points that I feel are important in class. I still find that I routinely need to create my own animated diagrams to explain processes in class. My colleague down the hall often uses third-party animated resources in his physics class, so it seems more practical in the long run to create something that can be reused, especially if it can be repurposed. My production becomes more like a textbook resource, and the better able it is to stand alone the more likely it is to be of value to other teachers and trainers.
To summarize, redundant objects must appear in each SCO in which the topic is relevant. It may be unrealistic, however, to expect or require a student to study the same material over again. An LMS might be able to handle this as long as the redundant material is meta-tagged as being equivalent in content and scope. In the example in Figure 8, student understanding of safety equipment is of paramount importance. You can see from the diagram that while the operation of a foundry furnace appears in only two of the three SCOs, the safety equipment sub-SCO appears in all three because the same safety equipment is appropriate for use with a burn-out kiln which appears in the SCO on investment molds. For this project the format and construction of the SCOs were much alike. In the future designers will want to be able to use SCOs from a wide variety of sources, and presumably these will vary tremendously in look, navigation and internal assessment style and quality. Redundancy will be an issue again, one potentially much more confusing to the user.
Equivalency of content
Redundancy in learning assessment is likely to be a large issue. In a recent SCO-building workshop held by the ADL Academic Co-Lab, each team independently assumed the need for internal assessment to establish the level of the users’ understanding of the material presented. This observation seems so reasonable that it is easy to expect the idea of internal assessment will become common. In the group I was working with, the scored assessment component was treated as a separate SCO, and this allowed for the easy removal of the assessment component — but this may not always be common practice. In SCO reuse situations where the original designer has included an assessment within the SCO, the new course designer must deal with the difference between the needs of the initial product and its assessment, and the assessment needs of the new course.
If the SCO can be easily and legally deconstructed the course designer might simply remove the assessment component. Or the course envelope, if responsible for all sequencing, might be designed to intercept and repurpose the value returned to the LMS from the assessment — for example as an un-scored practice quiz. The LMS might be used to repurpose the values returned, but if the course’s designer needs his or her own different type of assessment, or if no LMS is being used, something would have to be done to remove or neutralize the original quiz. It may well become a best practice to include assessments, quizzes and tests as easily removable components, or even as separate SCOs. (See Figure 9.)
FIGURE 9 Making assessment a removable component allows flexibility for designers who want to reuse a SCO
Some designers of sequential learning objects use the successful completion of some type of assessment as a prerequisite for continuing on within the SCO. Assume a designer wants to use several SCOs in a course, but the SCOs have each been designed by different authors and for different purposes. If the designer is including one of these SCOs because it contains information that is of interest but is not critical to the course, then it might be unreasonable to expect the new students to take and pass the quizzes within that specific SCO.
The need for best practices regarding redundancy
Redundancy of content in SCOs is to be expected; indeed, redundant material will often be required. The course designer will need a way to deal with the issues of duplicated content and duplicated or irrelevant assessments. Future best practices may suggest limiting in- SCO assessment (other than non-scoring practice quizzes) and find ways to shortcut or circumvent material duplicated across multiple SCOs within the same course.
This comes back to the issue of equivalency of content across the work of various developers writing multiple SCOs for multiple purposes. Obviously, for a teacher to find a SCO that meets his or her needs they will have to be able to judge the quality and relevance of the content of each SCO against any others. I can realistically review a certain number of textbooks each semester in order to decide which one would be most appropriate for a course, but I only choose one textbook per course (usually), I would expect to use several SCOs, perhaps dozens if they were small, covering single subjects. This problem will be multiplied when I am confronted with hundreds or thousands of available SCOs to choose from.
In order to exclude redundant material the designer is going to need to decide which version of the duplicated material is of the most value in this particular context. This may not be as simple as choosing one sub-SCO and circumventing the others with envelope sequencing instructions, as there may be aspects of several versions that the designer feels are of value.
Context Contamination: The reusability vs. context-rich learning object paradox.
For a learning object to be off-the-shelf ready it must be a completely standalone object. Since references to external material would involve connections to, and responsibility to provide, referenced external material, the presumption is that the complexity of such a reference system would get quickly out of hand, so objects conforming to the SCORM must be self contained. While course designers may like the efficiency of off-the-shelf content objects they also recognize the need to rework courses from semester to semester. One way to update content is to provide links to current, relevant external information. Additionally, often the self-contained units, while excellent as far as their designers envisioned them, may fail to provide material that is relevant to the course as a whole but which was beyond the scope of the individual SCOs. This will become more and more important as course designers find more creative ways to take advantage of existing SCOs.
The very stand-alone nature of the SCOs will tend to require the addition of contextual material within the course — material that is beyond the scope of the self-limiting SCO but relevant to the course as a whole. The very fact of self sufficiency will necessarily limit the size and complexity of the content. It is impractical to put an encyclopedia in each SCO.
Ellen Wagner, speaking to the ADL Academic Co-Lab gathering mentioned previously, pointed out that reusability and context often behave as opposites on a single continuum. (See Figure 10.) For a learning object or asset to be reusable it must be as flexible as possible. For a learning object to teach effectively it must provide context for its assets. For example, an image of the White House by itself is nearly context free and can serve a wide variety of learning objectives. When a designer builds an SCO that contains the image they add information or context. This might be historical information if the SCO is about American Civics or engineering details if the SCO is about period architecture. Engineering details are worthless to the political historian, however, so the addition of context limits the flexibility (the range of options for reuse) of the asset within another SCO. This tradeoff is fundamental to the concept of reusable learning objects.
FIGURE 10 The context vs. reusability paradox
An issue this paradox brings up is that of external reference. Computer learners have become accustomed to hypertext in research (the addition of links to information peripheral to the subject being directly addressed). Most have also become somewhat accustomed to “broken” links and 404 “Not Found” messages To link to a source outside of the SCO obviously reduces the reliable reusability of the SCO. Yet, course designers will need to update material each time a course is taught. Further, they may need to offer peripheral materials and additional resources for interested and motivated students. Somehow, they need to be able to allow students to access material not relevant to any individual SCO as it stands alone.
A prime example of a relevant, external resource would be a bibliography. Papers and books on subjects beyond the scope of any component SCO could be very relevant to the synthesis that is the goal of the entire course.
In the example course, the SCOs each contain a glossary of terms. Mostly these are foundry technical terms, not sculptural or art terms. None of the SCOs cover art history since this is peripheral to the intent and content of the processes being covered. Yet, for the overall course, there are terms to which the students need access, terms about forms and space, terms describing an artistic perspective. The glossary for the whole course, then, needs material not covered within any of the individual SCOs. Additionally, it may not be reasonable to expect all SCOs to contain glossaries, especially small SCOs and lower level aggregates.
As a result, within the envelope we find a need for any introductory material, basic instructions for the user and any or all of the following: sequencing information or controls, glossary, appendices, indexes, course assessments, practice tools, assessments of synthesis of multi-SCO components, resources, links and/or lists.
For a higher education asynchronous Web-delivered course, a dynamic web site, easily and quickly updateable, could serve to maintain the currency of the data yet utilize SCOs as functional learning objects, too.
Conclusion
Clark Aldrich writes that simulations are the wave of the future because the generation that includes most of my students has grown up with computers, with computer games, and with a new set of expectations of what constitutes learning. If he’s right, then it also follows that rich-media e-Learning will become the educational resource of choice, in school and out. The more that voluntary adult education becomes “skills based” rather than “degree based” the more relevant (and commercially viable) off-the-shelf learning objects will be. Government contracts aside, the more we want plug-and-play learning, the more relevant specifications like the SCORM become.
