Key takeaways
- Depth of Knowledge (DOK) is a four-level framework that describes the complexity of thinking a task requires.
- The four levels are: DOK 1 Recall, DOK 2 Skills & Concepts, DOK 3 Strategic Thinking, and DOK 4 Extended Thinking.
- DOK measures depth of thinking, not difficulty — a hard recall question is still DOK 1.
- It's the verb plus what you ask students to do with the content that sets the level, not the topic itself.
Depth of Knowledge, usually shortened to DOK, is a way of describing how complex a task is — how deeply a student has to think to complete it. It was developed by Norman L. Webb at the University of Wisconsin in 1997 to check whether state tests actually matched the thinking their standards demanded. Today teachers use it to plan questions, design assessments, and make sure a unit isn't stuck at pure recall.
The most important idea in DOK is also the one people get wrong most often: DOK is about depth, not difficulty. Asking a student to list all 50 U.S. state capitals is hard, but it's still Level 1 — it's recall. Asking them to use a single capital's location to explain a trade route is Level 2 or 3, because it requires reasoning. Difficulty is how much effort a task takes; depth is the kind of thinking it demands. This guide walks through all four levels with the verbs, question stems, and classroom examples that separate them.
The number of Depth of Knowledge levels, from Recall up to Extended Thinking.
Source: Norman L. Webb, 1997
The four DOK levels at a glance
| Level | What the student does | Sample verbs |
|---|---|---|
| DOK 1 — Recall & Reproduction | Recalls a fact, term, or simple procedure with one step | list, define, identify, calculate, label, recite |
| DOK 2 — Skills & Concepts | Uses information across two or more steps and decides how to approach it | classify, organize, estimate, compare, summarize, predict |
| DOK 3 — Strategic Thinking | Reasons, plans, and justifies with evidence; more than one answer is possible | justify, critique, hypothesize, cite evidence, draw conclusions |
| DOK 4 — Extended Thinking | Investigates and synthesizes across sources or subjects over time | design, synthesize, connect, prove, investigate, create |
What each level looks like in the classroom
DOK 1 — Recall & Reproduction
The student recalls a fact or follows a single, well-rehearsed procedure. There is one right answer and one obvious way to get it.
Question stems: "What is…?", "List the steps to…", "Define…", "Label the parts of…"
Example: Identify the verb in each sentence. Calculate 8 × 7. State the boiling point of water.
DOK 2 — Skills & Concepts
The student has to make a decision about how to approach the task and carry it through more than one step. The mental work is light reasoning, not just retrieval.
Question stems: "How would you classify…?", "Compare X and Y.", "What is the main idea of…?", "Estimate… and explain how you got there."
Example: Sort these 12 animals into vertebrates and invertebrates and explain your rule. Summarize a paragraph in one sentence. Read a bar graph to find which month sold the most.
DOK 3 — Strategic Thinking
The student reasons, plans, and defends a position. Tasks are more abstract, evidence matters, and there is often more than one defensible answer.
Question stems: "What evidence supports…?", "Justify your answer.", "How would you prove…?", "What is the best solution and why?"
Example: Use two sources to argue whether a character made the right choice. Design a fair test to compare two paper-towel brands. Decide which graph best represents a data set and defend it.
DOK 4 — Extended Thinking
The student investigates a complex problem over an extended period, pulling together ideas from several sources or subjects. This level rarely fits inside a single lesson.
Question stems: "Design an investigation to…", "Synthesize information from these sources to…", "Develop a model that…"
Example: Research local water quality, collect data over two weeks, and propose a solution to the city council. Write and revise an original short story that uses a studied author's technique.
DOK vs. Bloom's taxonomy: what's the difference?
Teachers often ask whether DOK and Bloom's taxonomy are the same thing. They're related but answer different questions. Bloom's names the type of cognitive process — remembering, understanding, analyzing, and so on. DOK names the depth and complexity of the task built around that process. A verb like "analyze" can sit at DOK 2 or DOK 4 depending on how much the student actually has to do. Use Bloom's to choose the kind of thinking; use DOK to check how demanding the task really is.
| Question | Bloom's taxonomy | Depth of Knowledge |
|---|---|---|
| What does it measure? | The type of cognitive process | The complexity and depth of the task |
| How many levels? | Six (Remember to Create) | Four (Recall to Extended Thinking) |
| Who created it? | Bloom, 1956; revised Anderson & Krathwohl, 2001 | Norman L. Webb, 1997 |
| Best used for | Choosing the kind of thinking in an objective | Auditing the rigor of questions and assessments |
How to use DOK when you plan
- 1
Start by naming the level you want
Decide before you write the question. A first-exposure lesson may sit at DOK 1–2; a project or performance task targets DOK 3–4.
- 2
Match the verb to the level
Use the verb lists above. 'List' and 'define' signal recall; 'justify' and 'design' signal strategic and extended thinking.
- 3
Check depth, not difficulty
Ask: is this hard because it takes effort, or because it takes deeper thinking? Adding more recall items raises difficulty but not DOK.
- 4
Build a ladder across the unit
Open with DOK 1–2 to secure the basics, then move to DOK 3, and finish with a DOK 4 task that pulls everything together.
- 5
Align the assessment to the level
If your task says 'design an investigation' (DOK 4), a multiple-choice quiz can't measure it. The question type has to match the depth.
Don't confuse depth with difficulty
A tricky recall question is still DOK 1. Raising the depth means changing the thinking, not just making the numbers bigger.
Most lessons need a mix
Aim for a spread, not all DOK 3. Students need recall and skills (DOK 1–2) before they can reason and justify (DOK 3–4).
The same verb can shift levels
'Explain' is DOK 1 if it means restate a definition, but DOK 3 if it means justify a conclusion with evidence. Read the whole task.
Use DOK to differentiate
Give the same content at different depths: some students classify examples (DOK 2) while others defend a rule with evidence (DOK 3).
Plan questions for every DOK level in minutes
Tell Kuraplan the topic and the depth you're targeting, and it drafts aligned objectives, questions, and activities.
Try the lesson plan generatorFrequently asked questions
DOK is a four-level framework developed by Norman Webb in 1997 that describes how complex a task is — how deeply a student has to think to complete it. The levels run from Recall (DOK 1) up to Extended Thinking (DOK 4).
DOK 1 Recall & Reproduction, DOK 2 Skills & Concepts, DOK 3 Strategic Thinking, and DOK 4 Extended Thinking. Each level asks for deeper, more complex thinking than the one below it.
No. Bloom's names the type of cognitive process (remember, understand, analyze). DOK measures the depth and complexity of the task. They complement each other — Bloom's helps you pick the thinking, DOK helps you check the rigor.
Difficulty is how much effort a task takes; depth is the kind of thinking it requires. Recalling 50 facts is difficult but still DOK 1. Justifying a conclusion with evidence is deeper thinking, so it's DOK 3.
No. Students need recall and skills (DOK 1–2) before they can reason at DOK 3–4. A strong lesson uses a mix, building from the basics up to strategic and extended thinking.