We can articulate C(T) with words and let the learner observe and interact with T

But, it may be better to let the learner observe and interact with a learning system, L

The learning system, L, should emphasize and expose aspects of the conceptual model

Goal: help students to develop an M(T) that approximates C(T) by using L

The learning system L should:

- Approximate T — faithfulness
- Express C(T)
- Abstracts away details of T
- Have muliple levels of abstraction
- Explicate the implicit
- Allows a higher degree of interaction than T allows
- Have greater transparency than T does