Physics · Scientific Investigation (IA)
IB Physics IA Grader
Upload your Scientific Investigation (IA) and get criterion-by-criterion feedback against the IB assessment criteria in the official IB Diploma sciences internal assessment criteria (scientific investigation, first assessment 2025). Whether you are at Higher Level (HL) and Standard Level (SL), iBacalao shows where your draft meets the mark scheme and what to improve before formative submission. Free to start in the Mac app; sign-in is required to keep reviews and usage limits tied to your account.
IB assessment criteria — 24 marks total
Your Scientific Investigation (IA) is graded against 4 criteria in the official mark scheme. iBacalao scores each one and tells you exactly where to gain marks.
Research Design
A research question described within a specific and appropriate context: variables (or correlated variables), the system it sits in, and directly relevant background theory. Methodological considerations explained — how variables are measured, scope and quality of the data, control variables, and safety/ethical/environmental issues. Enough procedural detail that the investigation could be reproduced.
Data Analysis
Recording and processing of data communicated both clearly and precisely — correct conventions for tables, graphs, units, decimal places and significant figures — with appropriate consideration of uncertainties, and processing relevant to the research question carried out appropriately and accurately.
Conclusion
A conclusion justified by the analysis — including the interpretation of processed data and its uncertainties — that answers the research question, and is justified through relevant comparison to the accepted scientific context (published values, theory), with traceable citations.
Evaluation
Specific methodological weaknesses and limitations explained — including their relative impact on the results — with realistic improvements that directly address the identified weaknesses.
Common mistakes to avoid
The most frequent reasons students drop marks on each criterion.
Research Design
- Research question stated without context, variables or background theory
- Method missing the detail needed to reproduce the investigation
- Control variables not identified, or how they were controlled not explained
- Safety, ethical or environmental issues ignored
Data Analysis
- Tables or graphs missing units, labels or consistent significant figures
- Uncertainties ignored or treated superficially
- Processing steps that can't be followed or contain errors
- Processed results that don't address the research question
Conclusion
- Conclusion claims more than the data can support
- No comparison with published values or accepted theory
- Uncertainties ignored when interpreting the result
- Sources cited too vaguely to be traceable
Evaluation
- Generic weaknesses ("human error") not specific to this methodology
- Improvements unrelated to the weaknesses identified
- No discussion of how much each weakness affects the conclusion
- Limitations of scope or of assumptions not considered
Common questions
How is the IB Physics Scientific Investigation (IA) marked?
Your Scientific Investigation (IA) is marked against 4 criteria totalling 24 marks using the official IB Diploma sciences internal assessment criteria (scientific investigation, first assessment 2025): Research Design (/6), Data Analysis (/6), Conclusion (/6), Evaluation (/6). Each criterion has its own mark bands, and your teacher's marks are moderated by the IBO.
What are the most common mistakes in the IB Physics Scientific Investigation (IA)?
The two criteria worth the most marks are where students lose the most. On Research Design: Research question stated without context, variables or background theory; Method missing the detail needed to reproduce the investigation. On Data Analysis: Tables or graphs missing units, labels or consistent significant figures; Uncertainties ignored or treated superficially. The full list for every criterion is above.
Which criterion is worth the most marks in the IB Physics Scientific Investigation (IA)?
The highest-weighted criterion is "Research Design" and is worth 6 marks. The top mark band for this criterion is the most detailed, so missing any element it mentions is the fastest way to lose marks.
What is the word limit for the Physics Scientific Investigation (IA)?
Word and page limits for the Scientific Investigation (IA) are set in the official IB Diploma sciences internal assessment criteria (scientific investigation, first assessment 2025) rather than being the same across subjects, so check your subject guide for the exact figure. Going over the limit risks examiners stopping at the limit and not marking what follows.
Can I use AI to help with my Physics IA?
The IBO allows AI for research support and feedback, but the submitted work must be entirely your own. iBacalao gives criterion-by-criterion feedback on your draft — the same kind of comment your teacher would give — without generating any text for your IA.