Hi, I have studied the SN book, but could NOT understand these two items. Please explain them for me. What does "Local Objective" mean? What does "Shared Global Objective" mean? Thank you.
In SCORM, objectives represent individual learning topics. For instance, in a course about playing soccer, there might be one learning objective for each of the following topics: ball control, goal keeping, soccer rules, and strategy.
That gives us three levels of granularity at which a learner's mastery and progress can be tracked. We can track progress on the entire course. We can track progress on the physical sections of the courses (SCOs). And, we can track progress on the conceptual topics being presented (objectives). You can think of these as a hierarchy of granularity. Course is the biggest, then SCO, then objective. A course contains many SCOs and a SCO contains many objectives. An objective that is part of a SCO is a local objective. To get more technical and concrete, in sequencing, a "local objective" directly maps to the run-time objectives reported by the SCO through the API and CMI data model.
There is a problem with this conceptual model though. In a given course, a topic (i.e. objective) might be addressed in more than one SCO. A topic might even be taught in more than one course. Thus the need for "global objectives". A global objective is a way for SCOs and courses to share their knowledge of a learner's mastery of a topic with one another. A global objective is a topic that is shared across SCOs and courses.
In SCORM 2004 sequencing, an activity can declare objectives in the manifest that can be used as inputs to sequencing and rollup rules. These objectives are associated with the activity directly and represent local objectives. At run-time, the SCO can read data from and write data to these local objectives.
A local objective in the manifest can also include a read map or a write map. These maps indicate that the local objective will read data from or send data to a global objective. A global objective is never explicitly declared. Simply creating a map from a local objective implicitly creates the global objective.
See also: Identifying a Global Objective vs. a Local Objective