A student who scores 68 out of 100 on a Cambridge IGCSE paper has no way of knowing, from that number alone, whether it's an A, a B, or a C — because Cambridge doesn't fix grade boundaries in advance. They're set after each exam session based on how that specific paper performed across all students who sat it. A raw score without a grade-boundary comparison tells you almost nothing about where a student actually stands.
Why IGCSE grade boundaries move every session
Cambridge sets grade boundaries after marking is complete, adjusting for that particular paper's difficulty relative to previous sessions — a harder-than-usual paper gets a lower mark threshold for each grade, and an easier one gets a higher threshold. This means the same raw score can translate to different grades across different sessions, and a student (or parent) reading a raw mock score without any grade-boundary context is essentially guessing at what it means.
Why this makes mock exam grading tricky to interpret without the right benchmark
- A generic percentage cutoff ("90% is an A") doesn't reflect how Cambridge actually grades, since real grade boundaries are rarely a round number and shift by paper and session.
- Comparing a mock score to last year's published boundaries is more useful than an arbitrary percentage, but still only an approximation, since this session's boundaries haven't been set yet.
- Without any boundary comparison at all, a student has no way to judge whether a 68 is comfortably an A or a worryingly borderline B.
How a mock series makes this useful instead of confusing
A mock exam series that benchmarks results against the most recent published Cambridge grade-boundary data — rather than reporting a bare percentage — turns a raw mock score into something closer to an actual grade prediction. That prediction is what a student needs to know whether they're on track for their target grade, or whether there's a real gap to close before the actual exam session.
What this looks like in practice
BuzzyBrains Academy's IGCSE Cambridge Test Series returns every mock result alongside a grade-boundary comparison based on the most recent published Cambridge data for that subject, so a raw score comes with a realistic sense of where it actually sits — A*, A, B, or a specific gap to close — rather than a number with no context.
The IGCSE Cambridge Test Series page has the full pack details — a useful next step if your child's current mock scores come back as bare percentages with no real sense of what grade they translate to.
