Across every subject, the same handful of mistakes appear year after year in Internal Assessments — and they’re rarely about a lack of subject knowledge. Most lost marks come from structural, procedural, or presentational errors that are entirely avoidable once you know what to look for. This article covers the mistakes that apply across subjects, regardless of whether you’re writing a science IA, a Math exploration, or a Business Management report.
1. A Research Question That’s Too Broad or Already «Solved»
Whether it’s Biology, Chemistry, Physics, or Math, a research question that’s too general leaves no room for a focused, deep analysis. «How does X affect Y» without specific, quantified variables and ranges signals a lack of planning before you’ve even started collecting data.
2. Not Enough Data Points or Repeats
Examiners consistently flag investigations with too few data points to draw a meaningful conclusion. As a general rule, aim for at least 5 levels of your independent variable with at least 3 repeats each (5 repeats is stronger) for experimental sciences, and for Math/AI explorations, aim for at least 20-30 data points where a statistical test is involved.
3. Choosing the Wrong (or No) Statistical Test
Presenting a graph and saying «there is a clear trend» is not sufficient at the higher grade bands in most science and math IAs. You need an appropriate statistical test for your specific data type, correctly applied and correctly interpreted — including stating what the result actually means for your research question, not just reporting a number.
4. Weak, Generic Evaluations
«A limitation was human error» is the single most common phrase examiners see — and the single most penalized, because it says nothing specific. A strong evaluation names a precise source of error, estimates its likely effect on the results, and proposes a specific, realistic improvement.
5. Ignoring the Word Count
Every IA type — science, Economics commentaries, Business Management, English — has a specified word count or page limit. Going over often means the excess is simply not read or assessed. Going significantly under usually signals underdeveloped analysis. Always check your specific subject guide for the current limit, since these are periodically updated.
6. Copying a Method or Structure Without Personal Adaptation
Examiners see the same handful of «textbook» investigations every session (marble chip reaction rates, pendulum period). Using a well-known method isn’t automatically penalized, but failing to adapt it in a way that reflects genuine personal engagement — a unique variable, a real-world connection, an unusual context — caps your Personal Engagement and Exploration marks.
7. Referencing and Academic Honesty Issues
Failing to properly cite sources — whether it’s a dataset, a background theory, or a direct quotation — is treated extremely seriously by the IB and can trigger an academic honesty investigation, regardless of subject. Always keep a running list of sources as you research, not just at the end.
8. Submitting Without Following the Command Terms in the Criteria
Every subject’s IA criteria use specific command terms (analyze, evaluate, discuss, justify). Students frequently describe when they should be analyzing, or analyze when they should be evaluating. Re-read your specific subject’s IA criteria descriptors before your final edit and check each section actually does what the command term requires.
9. Leaving It Until the Last Few Weeks
Rushed IAs are identifiable almost immediately — thin data sets, generic evaluations, no time for a second draft. The strongest IAs across every subject share one trait: the student had time to identify a flaw in their first attempt and fix it before the final submission.
10. Not Asking for Feedback Early Enough
The IB allows teachers to give general feedback on one draft before final submission. Students who submit a rough first draft weeks before the deadline — giving their teacher time to flag structural issues — consistently outscore students who submit a «final» draft with no prior feedback.
How to Use This List
Before you submit any IA, go through this list as a final checklist. Most of these mistakes take less than an hour to fix once identified — the real risk is not knowing they’re there until it’s too late to change them.