Content Design: Chunking and Sequencing

Content design is the art of outlining—of subdividing a course and then organizing it into proper pieces. It is system design, the art of grasping high level concepts, breaking up content into smaller units (chunking and decomposition of material into subclasses), and finally linking and relating these in a sequence and structure that makes sense to the end user. The process involves deconstructive as well as creative thinking.

I. Decomposition and Chunking: Differentiating Components

Decomposition: Separating into constituent parts.

—Webster's Dictionary

Chunk: A small but noteworthy piece of something, as in "a chunk of money."

—Webster's Dictionary

The Universe as Curriculum: Greek God as Instructional Designer

The Greek philosopher Anaxagoras believed that in the beginning a World Designer Mind ordered the universe by differentiating it into minute particles, then recombined these into a vast system. Anaxagoras's godlike World Mind was the first instructional designer, who differentiated, structured, and then sequenced the universe for humankind to wonder at and study as a "lifelong curriculum."

Aristotle, called by philosophers "the master of those who knew," best summed up the key steps in content design. The two steps in the process, he said, are:

1. Subdivide the material into the smallest intelligible chunks or units (today sometimes called "learning objects").

2. Link these units into a constituent logical structure (a hierarchical data structure, or tree diagram).

The subdividing process permits the logical storage of information, the linking process permits the ready access of that information.

Aristotle's first step is to spot subclasses in the material at hand. He cites as an example the subclasses of biology, where the genus (general family) of fish can be subdivided into specific subclasses, such as trout, bass, and salmon—and then further into species such as rainbow trout versus brook trout. The genus animal can similarly be subdivided into such subclasses as "human" versus chimpanzee, etc.

Aristotle goes on to describe how the entire domain of human knowledge, in fact, can be chunked into a hierarchy—a tree diagram upside down—with the most general family class at the top ("root"), reaching downwards through the branches and outwards through the subclasses and subsets (see Figure 2).

Figure 2: Aristotle and Systems— A Hierarchical Tree of Knowledge (Upside Down).

Aristotle's upside-down tree diagram may look simple, but it is a powerful tool. From Thomas Aquinas in the Middle Ages to Francis Bacon in the Renaissance, Denis Diderot in the Enlightenment, and John Dewey in modern times, systems thinkers and information architects have built upon it.

The real power behind the seemingly simple process of decomposition and hierarchical classification (top-down analysis followed by bottom-up synthesis) is that it provides a logical framework for a course. To illustrate how the concept of systems design lies at the heart of information design, let's look at the comparison of a corporate curriculum with the information structure of a typical book.

ROOT:	Corporate Curriculum	Book
BRANCHES:	Unit	Part
	Module	Chapter
	Lesson	Section
	Page (or Webscreen)	Page
	Line	Line

Information design for a course, as can be seen from this chart, is similar to the information design of a book or any other information vessel. Consider this brief story of the power of chunking in the evolution of information design throughout human history:

The Romans and the Sacrilegious Art of Chunking

Chunking is the key to powerful learning systems design, and yet has often been viewed as taboo.

• Moses and the Greeks: The Sacred Tablets and Scrolls Are Not to Be Chunked. In the beginning was the Word and the Word was the sacred tablet and the scroll. As examples of the magical new medium and technology of writing, the tablet and the scroll were not to be chunked. Moses didn't chunk the stone tablets carrying the Ten Commandments nor did the Greeks chunk Plato's scrolls. For a thousand years the medium of writing remained sacred, magical, and off-limits to chunking.

• The Romans Invent the Heretical Art of Chunking. Enter the Romans, who, being a generally uncultured, unruly, and unsuperstitious lot, held no beliefs about the sacredness of the medium of writing. They proceeded to chunk the scroll into "pages," which were then stitched together, thereby inventing the technology of the modern book. The book, they soon discovered, was fast, portable, and above all permitted random access to content. Chunking had finally begun its powerful march toward knowledge management. But one question remained: How was one to keep track of the content on all those pages?

• The Middle Ages: A Monk Invents the Search Engine. Another thousand years would pass before an enterprising monk would invent the final piece in the chunking puzzle: the search engine. This was the "index" (literally "pointing finger") to the book. The index listed topics in a book alphabetically and, much like the modern database, created instant random access to any specific page or desired topic ("learning object"). A powerful new information system was born. Yet one element was still lacking: rapid dissemination of the book.

• The Renaissance: A Scientific Revolution from Chunking and Indexing. Enter the invention of printing in 1450, which provided a high-volume global dissemination medium. At long last, small and timely pieces of scientific information could be stored (in an indexed book), retrieved, and disseminated. The scientific revolution of the Renaissance could now explode upon the modern world in full force, fueled largely by this new knowledge economy and its information machine—the chunked and indexed book flowing from printing presses all over Europe. The one-time stone tablet and the papyrus scroll, thanks to chunking, were now "pieces of information," forming a globally accessible database complete with search engine.

• Twenty-First Century: Chunking as Key to Learning Systems Design. Our modern corporate learning systems are direct descendants of the Renaissance information system, with its powerful notion of chunking and indexing (meta-tagging) coupled with rapid dissemination. And all of this because an ancient Roman dared to chunk a scroll. The moral: Creative new information technology and information design always depends on "committing sacrilegious acts," going against established doctrines and traditions.

II. Structuring and Sequencing: Linking Components

Sequence: a connected series.

—Webster's Dictionary

All things were undiscriminated unti
Intellect came and placed them in order.

—Anaxagoras, teacher of Socrates, 450 B.C.

After content has been deconstructed into units, it needs to be structured and sequenced. This step is what Aristotle refers to as the linking or associating of components, and it can be of two types: simple linking (occurring within the same class, as in linking sales techniques with sales techniques) or composite linking (occurring between different classes, as in linking sales techniques with presentation techniques). In what follows we list seven types of sequencing.

Information Structures: Sequencing a Course

There are four basic structures of information: linear, branching, spiral, and scenario-based. Each of these structures comes into play where appropriate: linear for a course on a new product, branching for interactive simulations, spiral for a course on programming (circling upwards and building on what has already been learned), and scenario-based for a case study.

Built within these four structures are the varieties of actually sequencing material in a course. We list six basic ways of sequencing a course here.

Linear:

• Alphabetical

  Example: Online performance support systems. Typically alphabetical lists of topics or frequently asked questions.

• Chronological, Step-by-Step, or Procedural

  Example: Consultative selling skills (an overview, then stepwise instructions through the process).

• Known-to-Unknown

  Example: A suite of classes divided into "beginning, intermediate, and advanced" modules, each having as a prerequisite the previous class.

Branching:

• Core-and-Electives

  Example: Dividing a curriculum into required courses (core) and electives (branch-offs).

Spiral:

• Easy-to-Difficult (Simple-to-Complex)

  Example: The typical way we learn a foreign language, beginning with easy words and progressing to more difficult ones. Sometimes called the cumulative approach or elaboration theory. (See Comenius.)

Scenario-based:

• Solve-the-Problem

  Example: Simulations. A problem is presented to the student to capture attention and focus them on the steps necessary to solve it. This design structure supplies goal and motivation at the same time. It is sometimes referred to as problem-centered design or goal-driven scenarios and is a classic technique, one recommended by most major learning theorists. (See Comenius, Rousseau, and Dewey.)

None of these sequencing structures are absolutely distinct and separate from one another. Often more than one technique will be used in a course.

See also Systems: An Architecture of Continuous Learning Systems