Internal assessment (IA)
The IA is an Individual investigation marked by the teacher and moderated by the IB. It is intended as a creative, meaningful student investigation. The only time in the DP Biology course where you get to be a biologist, to ask a question, make a prediction and collect data to test (or falsify) your hypothesis. The best students make this an insightful and ethical investigation.
Teachers and examiners want students to demonstrate the use of their skills, asking the right question, designing a data collection method, analysing data, concluding and evaluating.
Asking the right question and designing method is called “Research design” and is worth 25% of the marks.
Data presentation and analysis includes the ability to put data into a clear table of results, following scientific conventions of units and uncertainties, to draw a graph, or do some processing of the raw data, then to perform a statistical test. This counts for 25% of the marks.
Concluding and evaluating are very important in the investigation. The ability to describe the data and to draw conclusions, then to justify how the data supports the conclusions, identify limitations and suggest realistic improvements to the investigation counts for 50% of the marks.
For assessment purposes your teacher will probably give you an overall structure to follow for the IA report. Checklists also help ensure all the important sections are included.
Small groups can work together during the early stages of planning an investigation, but this it limited to three in a group, and really only applies to the practical methods of choosing and using equipment. Teacher's decide whether or not to allow this.
The "individual" part is that everyone must investigate a unique research question. You must chose a unique combination of independent variable and dependant variable, different to every other student in the class. The research question must be individual.
Approximately twelve pages of report with a 3000 word limit. The page number isn't fixed so it's OK to take space for diagrams, or include whole page graphs with tables of raw data and processed data. There is no advantage squishing diagrams or tables into a postage stamp sized image to save space, they don't count in the word limit.
The method could be any of the following:
- a practical lab experiment.
- analysis of data taken from a database.
- a field course to collect data.
- a hybrid practical lab with analysis of secondary data.
- an investigation using an open-ended simulation.
All investigations will have the following sections to fulfil the assessment criteria:
- Research design
- Background information.
- Research question.
- Controlled variables.
- Experiment method (or a design for secondary data collection)
- Discussion of safety, environmental impact and ethics.
- Data Analysis
- Data presented in tables - following scientific conventions.
- Consideration of uncertainties.
- Graphs and other data processing.
- An appropriate statistical test.
- Conclusion
- Data interpretation.
- Conclusion - described and justified by data.
- Relevant comparisons made to the scientific context for further justification.
- Evaluation
- Discussion of relevant weaknesses.
- Description of the relative impact of these limitations.
- Suggestion of realistic improvements.
- Descriptions of details of the improvements.
The investigation should account for approximately 10 hours of work, including lab work and write-ups.
It is possible to complete an investigation using database data, which counts as data collection and should be carefully selected to show control of other variables, in the same way as practical work.
This is an example outline plan of lessons for 10 hours of Investigations.
Timings / hours | Outline of activities |
1-2 | Introduction to the task & student choice of topic / research question. Optional time for collaboration or testing the methods, initial planning of the IA. Homework: Preliminary research for scientific context. Investigation proposal form |
3-4 | Teacher consultation time - usually teachers check the feasibility of the RQ. Writing the introduction, research question, scientific context & methods. |
5-8 | Lab experiment time / data collection. Analysis of data & conclusion writing. Opportunity to overcome any obstacles. Ask your teacher for guidance, if you need to. |
9-10 | Finish the conclusion and evaluation. Hand in the first draft. |
11-12 | Written feedback on first draft - this is only allowed once. Final revision and redrafting. |
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