What is Depth of Knowledge?
Depth of Knowledge, or DOK, is a framework that describes the level or complexity of thinking that is required to complete an activity. The Depth of Knowledge framework was introduced by Dr. Norman Webb in 1997, with the goal of moving learners beyond simple surface-level understanding and memorization to more sophisticated and contextualized higher-level thinking skills. Depth of Knowledge differs from Bloom’s Taxonomy, which categorizes cognitive processes by evaluating the cognitive demand required to complete a task. While easy to conflate, Webb’s DOK is not equated to difficulty or effort: a hard task can require low DOK, while an easy task can require high-level DOK thinking.
The four levels of Depth of Knowledge
When it comes to the Depth of Knowledge (DOK) framework, there are four levels, from DOK 1 to DOK 4, to describe the cognitive complexity of a task. This framework is key in both designing and reviewing educational activities.
- Level 1—DOK 1: Recall & Reproduction focuses on the ability to recall information. Students retrieve information like facts, definitions, and simple procedures from memory.
- Level 2—DOK 2: Skills & Concepts is where students demonstrate understanding by applying skills, making decisions, and explaining their ideas or steps.
- Level 3—DOK 3: Strategic Thinking requires students to use reasoning to justify, argue, or develop a plan of their choosing, since in many cases there might be more than one “right” answer.
- Level 4—DOK 4: Extended Thinking takes time and may include several lessons, in which students engage in complex, multi-step processes. These tasks often involve research and may require iteration if a first idea fails.
Let’s take the scientific concept of the water cycle as an example to illustrate these points:
- DOK 1 might involve defining the four basic stages: evaporation, condensation, precipitation, and collection/runoff.
- DOK 2 may require students to explain how one stage moves into the next.
- DOK 3 could ask students to predict what might happen to the stages if a drought occurs.
- DOK 4 could challenge students to design a solution for a community suffering from such a drought.
Depth of Knowledge vs. Bloom’s Taxonomy
Bloom’s Taxonomy is a staple framework for teachers who aim to move their students from lower-order thinking skills to high-order thinking skills. These six categories (and related action verbs) help teachers design learning activities that progress from basic knowledge acquisition to more complex problem-solving and creation skills: remember, understand, apply, analyze, evaluate, create. Webb’s DOK goes beyond naming the type of thinking: 1. Recall & Reproduce, 2. Skills & Concepts, 3. Strategic Thinking & Reasoning, 4. Extended Thinking. The four levels of Depth of Knowledge encourage teachers to evaluate the evidence of learning by continually checking the depth and context of a particular task.
Why Depth of Knowledge matters in instruction and assessment
Depth of Knowledge is not about moving sequentially through the lessons. Instead, a well-designed lesson will require students to move between levels more than once. DOK is strongest when the assessment aligns to the lesson, meaning that the assessment items reflect the cognitive demand of the instruction. Misalignment can result in students being unprepared to meet standards. Whether using formative assessment or summative assessment methods, the DOK-aligned evidence should not just be about recording performance, but it should also be used to inform future teaching strategies. A shared understanding of DOK between classroom teachers and support staff ensures the instructional rigor needed to showcase student achievement, whether on classroom assessment or state testing.