Composite LearningUnits

[Elscha]

Actual Situation

We can only model LearningUnits, which do not include/reference further units directly.

Target Situation

We want to model LearningUnits that reference/include other LearningUnits in one block. These blocks should not be split up into several separate blocks by the path planning algorithm and may contain additional units, e.g., an additional introduction at the beginning and an additional exercise at the end of the block.

Purpose

This should allow the user to model chapters inside a learning path. For instance, a chapter about loops, which includes:

• An introduction at the beginning about what are loops and for what are they used for
• 4 units about loops: WHILE, DO WHILE, FOR, FOR EACH
• An additional exercise at the end at which the user has to choose which loop fits best for a given situation or to program an algorithm without explicitly specifying the usage of one of the loops (the user has to decide).

Type Modifications

We need a new type CompositeUnit, which refer to an arbitrary amount of nested LearningUnits but also CompositeUnits. The class structure needs to be adapted so that we can use polymorphism to return the skills:

• A LearningUnit should return its skills
• A CompositeUnit should not return/contain any new skills. Instead it should return the skills of the nested elements

Modifications to the Algorithm

The algorithm should try not to break the CompositeUnits. Therefore, it should first try to find a path by considering the CompositeUnits as one single item. After a path was detected, the algorithm may find a sub path recursively inside each of the used CompositeUnits. Further, LearningUnits that are used inside a CompositeUnit must not be used be passed separately to the algorithm (otherwise the algorithm will treat them as alternative and may break the structure).

[Elscha]

Open Questions

Additional Taught/Required Skills of the CompositeUnit

Should CompositeUnits only return the taught/required skills of the nested LearningUnits or may they define additional skills? For instance: May teach a CompositeUnit additional skills regarding "The Introduction of Loops" and "Choosing Among Loops" or must they be included by adding additional LearningUnits?

Advantages of Additional Skills

• More flexibility while creating CompositeUnits

Disadvantages of Additional Skills

• More checks required (nested skills must not require skills of the parent)
• Skills provided via CompositeUnits cannot be learned via the nested LearningUnits only

Proposal

CompositeUnits may not define additional taught/required skills.

What Skills Should be Displayed for a CompositeUnit

When returning the taught/required skills of a CompositeUnit, the following skills should be returned (needs to be clarified):

• Required Skills: The sum of the required skills of the nested LearningUnits, which are not taught by other nested LearningUnits. Otherwise, requirements of the CompositeUnits won't be fulfillable.
• Taught Skills: The sum of all taught skills of the nested LearningUnits, including skills that are required inside the CompositeUnit. Reason: Some other skills outside of the CompositeUnit may also require intermediate skills as required input.

For instance, given the following CompositeUnit with its nested elements:

SK:10 and SK:11 should be marked as requirements, SK:21, SK:22, and SK:23 should be marked as taught skills.

Teaching parts of a CompositeUnit

Can a CompositeUnit be split into its nested elements?

Proposal

It should be possible, iff only a supset is to be learned, otherwise its kept as complete block. Or more general:

1. First add the composite and place the complete CompositeUnit at the path
2. Do not split the CompositeUnit. Otherwiese there won't be a use case to model such elements. I.e. avoid that other LearningUnitswere added between "Introduction of Loops" and "While Loop" if they are part of a CompositeUnit.
3. Find a path inside the CompositeUnit:
   1. Bring the nested Elements into an order
   2. Remove unrequired elements

Consequence

This allows:

• Composites to be learned as one block
• Composites may bring additional nested elements (by defining a course goal or by adding dependencies among the nested elements)
• Nested elements may be learned without the parent, if a different goal was specified. E.g.:
  • Goal for the composite: "Introduction of Loops", "While", "Do While", "For", "For Each", "Choosing among Loops"
  • Goal for one nested element: "For", which may also require "Introduction of Loops"

[Elscha]

Discussion moved to e-Learning-by-SSE/nm-concept#21