Webb’s Depth-of-Knowledge (DOK)

Norman L. Webb, a senior research scientist and mathematics educator from the University of Wisconsin-Madison (Webb, 1997), developed a process and criteria for systematically analyzing the alignment between curriculum standards and assessments. This body of work offers educators a model to analyze the cognitive expectation demanded by standards, curricular activities and assessment tasks. Each grouping of tasks reflects a different level of cognitive expectation, or depth of knowledge, required for the student to complete the task or respond in an acceptable manner.

The following table reflects an adapted version of the model.

DOK LevelTitle of LevelDescription of LevelNotes on Items Written for These Levels
1Recall and ReproductionRecall of a fact, information, definition, term or performance of a process or procedure.Items typically specify what the student is to do, which is often to carry out some procedure that can be performed mechanically.
2Skills and ConceptsIncludes the engagement of some mental processing beyond recalling or reproducing a response.Items require students to make some decisions as to how to approach the question or problem.  These actions imply more than one mental or cognitive process/step.
3Strategic ThinkingRequires deep understanding as exhibited through planning, using evidence, and more demanding cognitive reasoning.  The cognitive demands are complex and abstract.Items require students to justify the responses they give and may have more than one possible answer.
4Extended ThinkingRequires high cognitive demand and is very complex.  Students are expected to make connections and relate ideas within the content or among areas — and have to select or devise one approach among many alternatives on how the situation can be solved.Items require students to bring together skill and knowledge from various domains.  Due to the complexity of cognitive demand, this level often requires an extended period to answer.  A DOK 4 is first a DOK 3 with added connections.

As DOK levels are assigned to standards and course objectives, the following served as general guidelines for developers of this model:

  • The DOK level assigned should reflect the level of work students are most commonly required to perform in order for the response to be deemed acceptable.
  • The DOK level should reflect the complexity of the cognitive processes demanded by the task as outlined by the objective, rather than its difficulty. Ultimately the DOK level describes the kind of thinking required by a task, not whether or not the task is “difficult.”
  • The DOK level should be assigned based upon the cognitive demands required by the central performance described in the objective.
  • The objective’s central verb(s) alone is/are not sufficient information to assign a DOK level. Users of this model must also consider the complexity of the task and/or information, conventional levels of prior knowledge for students at the grade level, and the mental processes used to satisfy the requirements set forth in the objective.

Web resources and test examples:

Webb’s Alignment Information: Depth of Knowledge Levels Explained & Sample Test Items

Nebraska Department of Education: Assessment Division:

Kentucky Department of Education:  Support Materials for Core Content for Assessment:

Webb, N. (1997). Research monograph number 6: Criteria for alignment of expectations and assessments on mathematics and science education. Washington, D.C.: CCSSO.