Extended Essays - overview

What is the Extended Essay?

"The Extended essay is intended to promote academic research and writing skills, providing students with an opportunity to engage in personal research in a topic of their own choice, under the guidance of a supervisor. This leads to a major piece of formally presented, structured writing, in which ideas and findings are communicated in a reasoned and coherent manner, appropriate to the subject chosen. It is mandatory that all students undertake three reflection sessions with their supervisor, which includes a short, concluding interview, or viva voce",
IB Extended essay website 2020

Key points about Biology Extended Essays

Great things about the Extended Essay in an IB diploma

  • Students get some choice in their topic and can follow a personal interest.
  • It really is a useful learning experience for anyone going to university as the formal structure resemble a dissertation.
  • It's a great opportunity to teach academic honesty, use of citations and referencing. Ref: IB guidance on Effective citing and referencing.
  • The reflection sessions can help students to become aware of their own thinking and learning strengths and weaknesses.
  • Students are often proud of their work, and have a sense of achievement once it's completed.

Schools are required by the IB to provide an Extended Essay Supervisor to each student.
The roles of the supervisor include.

  • To guide the student in the choice of topic and research question.
  • To give a structure to the three reflection sessions and encourage students to think critically about the writing process.
  • To oversee students writing comments, each of approximately 150 words, in the same language as the essay) on the 'Reflections on planning and progress form', RPPF.
  • To comment on one full draft of the essay.
  • To carry out a viva voce with the student
  • To confirm authenticity of the work.
  • To write a final supervisor's comment on the RPPF.

Particular hurdles for Biology Extended Essays

  • The choice of extended essay subject and it's treatment in the essay must be biological.
  • Collecting data can sometimes take more time than expected.
  • Finding data from secondary sources is often quite challenging, especially demonstrating controlled variables.
  • Ethical and animal experimentation guidelines, IB Guidelines for the use of animals in IB world school should be followed in any extended essay.
  • No experiments can be planned that cause pain or suffering to any animal.
  • Written consent must be given by participants of any experiment involving humans.


  • The extended essay is marked out of 34
  • There are five criteria; Focus and method, Knowledge and understanding, Critical thinking, Presentation and Engagement.
  • A grade is awarded from E to A
  • The grade boundaries for grade D is 7 marks, grade C is 14 marks and grade A is 27.

Resource for teachers and students

Guidelines for the use of animals

The guidance says that in all IB work we should consider, replacing the animal with a simulation, refine the experiment to alleviate any stress on the animal or reduce the number of animals involved.

"Any investigation involving animals should initially consider the replacement of animals with cells or tissues, plants or computer simulations. If the animal is essential to the investigation, refinements to the investigation to alleviate any distress to the animal, and to reduce the numbers of animals involved, should be made.

Experiments involving animals must be based on observing and measuring aspects of natural animal behaviour. No experimentation should result in any cruelty to any animal—vertebrate or invertebrate. Therefore, experiments that administer drugs or medicines, or those that manipulate the environment or diet beyond that which can be regarded as humane, are unacceptable in IB schools."

IB Guidelines for the use of animals in IB world school

Suitable topics for Extended Essays in Biology

An essay in Biology needs to be based on some experimental data, either collected through a student designed investigation or primary data provided from another source. Students should avoid super-sophisticated university laboratory-based experiments as the examiner is likely to suspect that the design of the investigation, the process of data collection and interpretation of the data is not that of the student. Actually, simple investigations that students can do at home can be very successful. Descriptive essays will not be appropriate for earning higher marks.

The topic of the essay must lie clearly within Biology and not lean into other subjects. So what does this mean? Biology is the study of life,so the essay must deal with living organisms. Biochemical topics can be pursued but must be focussed on the effects on the living thing not the chemical aspects. For example, a study of enzymatic kinematics falls under chemistry but the factors that affect enzymes and how this impacts on the ecological niche of an organism becomes a Biology topic. An Essay which deals with how organisms learn to negotiate a maze is more likely to be considered as Psychology but if the behaviours are related to the survival of the organism then this falls towards Biology.

To read more about choosing a topic for the extended essay in Biology read the InThinking page  Extended Essay titles.

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