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EE Playbook

Biology EE Criteria Guide

Develop an independent biological question with strong subject knowledge, sharp critical thinking, and disciplined structure.

Use this guide to keep the Biology Extended Essay focused on a precise question, accurate biological terminology, evidence-based analysis, and a polished presentation that supports your argument from start to finish.

Biology EE

Assessment criteria

See what each criterion measures, how many marks it carries, and what stronger evidence usually looks like.

This is Marksy's independently written criteria explanation, not an official IB publication.

Criterion A: Focus and Method (6 marks)

How clearly the Biology essay defines a focused research question and uses a suitable research method.

Stronger evidence

The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Early-stage evidence

Only fragments of relevant evidence are visible. The response begins to address focus and method, but important parts remain missing, unclear, or unsupported.

Criterion B: Knowledge and Understanding (6 marks)

How accurately the essay uses Biology knowledge, concepts, terminology, and research context.

Stronger evidence

The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Early-stage evidence

Only fragments of relevant evidence are visible. The response begins to address knowledge and understanding, but important parts remain missing, unclear, or unsupported.

Criterion C: Critical Thinking (12 marks)

How effectively the essay selects evidence, develops analysis, evaluates material, and builds a reasoned answer.

Stronger evidence

The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Early-stage evidence

Only fragments of relevant evidence are visible. The response begins to address critical thinking, but important parts remain missing, unclear, or unsupported.

Criterion D: Presentation (4 marks)

How well the essay's structure, academic conventions, citations, and visual material support the research.

Stronger evidence

The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Early-stage evidence

Only fragments of relevant evidence are visible. The response begins to address presentation, but important parts remain missing, unclear, or unsupported.

Criterion E: Engagement (6 marks)

How specifically the reflections show decision-making, adaptation, and learning during the research process.

Stronger evidence

The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Early-stage evidence

Only fragments of relevant evidence are visible. The response begins to address engagement, but important parts remain missing, unclear, or unsupported.

Markband guide

Criterion A: Focus and Method (6 marks)

MarksWhat the draft currently shows
0The submitted material does not provide assessable evidence for focus and method.
1-2Only fragments of relevant evidence are visible. The response begins to address focus and method, but important parts remain missing, unclear, or unsupported.
3Some relevant evidence is developed, although the response is inconsistent or leaves important connections unexplained.
4-5The response addresses the criterion securely in most places, using relevant evidence and generally clear reasoning, with limited gaps.
6The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Criterion B: Knowledge and Understanding (6 marks)

MarksWhat the draft currently shows
0The submitted material does not provide assessable evidence for knowledge and understanding.
1-2Only fragments of relevant evidence are visible. The response begins to address knowledge and understanding, but important parts remain missing, unclear, or unsupported.
3Some relevant evidence is developed, although the response is inconsistent or leaves important connections unexplained.
4-5The response addresses the criterion securely in most places, using relevant evidence and generally clear reasoning, with limited gaps.
6The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Criterion C: Critical Thinking (12 marks)

MarksWhat the draft currently shows
0The submitted material does not provide assessable evidence for critical thinking.
1-3Only fragments of relevant evidence are visible. The response begins to address critical thinking, but important parts remain missing, unclear, or unsupported.
4-6Some relevant evidence is developed, although the response is inconsistent or leaves important connections unexplained.
7-9The response addresses the criterion securely in most places, using relevant evidence and generally clear reasoning, with limited gaps.
10-12The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Criterion D: Presentation (4 marks)

MarksWhat the draft currently shows
0The submitted material does not provide assessable evidence for presentation.
1Only fragments of relevant evidence are visible. The response begins to address presentation, but important parts remain missing, unclear, or unsupported.
2Some relevant evidence is developed, although the response is inconsistent or leaves important connections unexplained.
3The response addresses the criterion securely in most places, using relevant evidence and generally clear reasoning, with limited gaps.
4The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Criterion E: Engagement (6 marks)

MarksWhat the draft currently shows
0The submitted material does not provide assessable evidence for engagement.
1-2Only fragments of relevant evidence are visible. The response begins to address engagement, but important parts remain missing, unclear, or unsupported.
3Some relevant evidence is developed, although the response is inconsistent or leaves important connections unexplained.
4-5The response addresses the criterion securely in most places, using relevant evidence and generally clear reasoning, with limited gaps.
6The response addresses the criterion consistently and precisely. Evidence is well selected, reasoning is sustained, and important choices or limitations are handled convincingly.

Build Sequence

Did You Know? Most weak drafts fail from sequence chaos, not lack of ideas.

Step 1

Lock a narrow question

Choose a biological topic that is researchable, specific, and clearly linked to the subject.

Step 2

Build subject knowledge first

Use accurate terminology and relevant theory so the essay sounds like biology, not general science.

Step 3

Argue from evidence

Weave findings, comparisons, and evaluation into a coherent line of reasoning instead of stacking summary paragraphs.

Step 4

Finish with presentation discipline

Make the layout, citations, and reflective elements clean enough that the assessment can reward the thinking rather than be distracted by format issues.

Submission Checklist

  • Research question is specific, focused, and biologically valid.
  • Terminology and concepts are accurate throughout.
  • Evidence is interpreted rather than merely described.
  • Presentation and engagement are both visible in the final draft.

Quick Wins

  • Draft a one-sentence thesis that answers the question before expanding the essay.
  • Use source notes to separate biological fact, interpretation, and evaluation.
  • Check each paragraph for a clear link back to the research question.

Did You Know?

Get Rubric Feedback On Your Biology EE Draft

Upload your Biology Extended Essay draft to Marksy and get independently written feedback on focus, knowledge, critical thinking, presentation, and engagement. Every criterion mark is an estimate, not an official result. The result includes an estimated mark for every criterion, evidence from your draft, and the changes to make first. Your final mark may differ after teacher assessment or external moderation.

1. Upload your EE draft PDF to Marksy.
2. Get an estimated mark and feedback for every EE criterion.
3. Revise and resubmit with focused improvements.
Marksy grading results view

Instant Grading Results

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Marksy criterion feedback highlights

Criterion-By-Criterion Feedback

See the estimated mark, evidence, and next step for every assessment criterion.

Marksy list of fixes for an IB draft

Action List To Improve

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Marksy AI detection and highlight review

Confidence And Integrity Signals

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