| A Critical Look at Learning Objectives and Assessments
By Steven B. Just
Valid criterion-referenced testing theory instructs
us to closely tie test questions to learning objectives (Criterion
Referenced Test Development, Shrock and Coscarelli, 2007).
There is unassailable logic here: The learning objectives
define the scope of what the student is to learn and the test
questions ensure the acquisition of this knowledge.
But, as the saying goes: “In theory there
is no difference between theory and practice, but in practice
there is,” and I have growing reservations about
this practice. Apparently at least one other person
also feels this way. Will Thalheimer, in his very positive
review of the latest edition of the Shrock and Coscarelli
book, states in his blog (www.willatworklearning.com) :
They use the methodology of relying on a
single objective to guide the process of both instructional
design and evaluation. I am now advocating to free instructional-design
objectives from the crazy constraint of being super-glued
to the evaluation objectives.
Let me first say that I am all for using learning
objectives (albeit with caveats) and I understand the need
to tie evaluation back to instruction, but let me point out
just a few practical problems that result
from a literalist adherence to this methodology.
Which Learning Objectives Do We Test On?
Let’s look at a typical (print-based or
online) learning system. (I am most familiar with the learning
systems used in the pharmaceutical industry so I’ll
use these as an example.) In the pharmaceutical industry,
learning systems generally consist of a number of modules
(typically five to seven). Each module is further divided
into lessons or sections (five to ten, sometimes more). Each
lesson then begins with its requisite learning objectives
(usually around five to ten). So, in the learning system as
a whole there are generally anywhere between 125 and 700 distinct
learning objectives.
For formative evaluations at the module level
it is sometimes practical to test on every learning
objective — as the theory tells us we are supposed to
— but what do we do for the final summative evaluation?
Short of giving a 300 question test or giving multiple summative
exams (as many as seven if you do the math – see below)
the only practical solution is to test on some learning objectives
and not others. In effect, we are forced to conclude that
some learning objectives are more important than others —
some become nice-to-knows and others become need-to-knows.
This is not always palatable but it’s the only practical
course of action.
How Many Questions Does It Take to Test a Learning
Objective?
For practical reasons we usually like to give
tests that are no longer than an hour or so. If we give the
students 60 to 90 seconds per question, the test can then
only have 40 to 60 questions — let’s say 50, which,
in my experience, is a typical summative exam length. So that
means we’ve somehow whittled our 300 learning objectives
down to the 50 that we are going to test on. This means that
we have excluded 250 learning objectives from our summative
evaluation. That’s an awful lot of nice-to-knows!
Not ideal, but let’s assume we’ve done that. We
now have 50 learning objectives and 50 questions, or one question
per learning objective. Two obvious problems present themselves:
- Is one question enough
to test a learning objective? The answer here is sometimes
yes, often no. And even if one question “covers”
the objective, is one question enough to ensure —
taking guessing and the standard error of measurement into
account – that the student has truly “mastered”
the objective? Doubtful.
- If we adhere to the
notion that each need-to-know learning objective
is independently critical knowledge that must be mastered
this implies that the passing score on the test must be
100%! Why? Any score less than 100% means that the student
has not mastered at least one element of need-to-know
knowledge.
Can We Please Test Above the Knowledge/Recall
Level?
We all know that most tests are written at the
Knowledge/Recall level of Bloom’s Taxonomy. And we all
know why: It’s hard and time consuming to write higher-level
questions. And there’s another reason: Learning objectives
let us off the hook.
How are learning objectives our Recall enablers?
The logic goes like this:
- We know from valid-testing
theory that questions need to be written to learning objectives.
- What level of Bloom’s
are most learning objectives written at? Knowledge, of course:
“You will be able to state…” “You
will be able to list…” You will be able to name…”
“You will be able to define…” (The learning
objectives that I see are usually very narrowly written.)
- So, we follow valid-testing
theory and write the corresponding questions to the narrow
learning objectives – at the Knowledge/Recall level.
- We’re just doing
what theory tells us to do.
What is To Be Done?
Thalheimer has the right idea: Let’s decouple
learning objectives from evaluation objectives. Writing independent
evaluation objectives provides several benefits:
- It will permit us to
write fewer, critical, broader objectives on which to test.
- Because there will
be fewer, broader objectives we can actually have several
— or sometimes many — questions per objective,
permitting a student to miss a question or two on an objective
without failing to master the entire objective. Or, put
another way, we can have a legitimate passing score of less
than 100%.
- We can take this re-writing
opportunity to write the evaluation objectives — and
thus their corresponding questions — at higher Bloom’s
levels.
Writing a separate set of evaluation objectives
adds a step to the process (i.e. it’s more work) but
it does address the practical problems that arise from the
traditional learning objective-based methods.
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