A share of the final grade in almost every IB subject is earned before the exam period begins. That share is the Internal Assessment, and it is the most controllable part of the diploma.
The part of the grade won before the exams
The weighting varies by subject and level and is published in each subject guide. In several subjects it is large enough that the difference between a weak and a strong Internal Assessment moves the final grade by a full band.
Because it is produced over months rather than in three hours, it rewards planning in a way that examinations do not.
The teacher marks, an external moderator checks
The subject teacher awards the mark against published criteria. A sample is then sent for external moderation, and the moderator can adjust the whole cohort's marks up or down.
This is why writing to the criteria matters more than writing something the teacher will like. The criteria are published and can be read directly.
Topic choice decides the outcome
More Internal Assessments are damaged by the topic than by the writing. A topic that is too broad prevents the required depth; a topic that is too narrow does not generate enough to discuss.
The test worth applying is whether the criteria can each be satisfied with the chosen topic. Where one criterion has nothing to attach to, the topic is wrong, and that is far cheaper to discover before the work starts.
The calendar runs across the year
Internal Assessments in six subjects do not arrive together, but their drafting periods overlap, and they overlap with the Extended Essay.
Schools publish internal deadlines that sit well before the official ones. Treating the official deadline as the real one is how students end up writing three assessments in the same fortnight.
The most common mistake
Starting to write before the criteria have been read. The work then has to be reshaped afterwards to fit them, which takes longer than reading them first and produces a weaker result.