Student learning outcomes should be measurable. They key to both in-class and online assessment is understanding how to measure course activities. The following are examples and ideas for how this can be done.
Determine measurable evidence
During the course design process, determine what kinds of measurable evidence the student will provide through the performance of some learning outcome.
One example of online evidence of student learning is: the student will write thoughtful and well-written online discussion board posts. First, the phrase "thoughtful and well-written" would need to be defined in a grading rubric so as to be measurable, for example, by describing such a post as one that:
Makes a clearly articulated claim
Supports that claim with evidence
Engages other discussion board posts in order to situate the post within the class discourse.
Next, much like you would grade students' traditional paper assignments, you would grade these discussion board posts accordingly. This example of online evidence has much in common with traditional evidence of student learning.