Why students lose marks they actually knew

Your child can lose marks on an answer they understood. The examiner gives marks only for what is written on the page, point by point, against the board's marking scheme. A step kept in the head, a unit left off or a reason never written earns nothing. The fix is in how the answer is written.

Why do students lose marks even when they know the answer?

Because the examiner marks the page, not the child. Every board paper comes with a marking scheme - the board's list of what earns each mark. It breaks each answer into value points and says what each one is worth. What a marking scheme contains, and how to read one shows a real page of it.

CBSE tells its examiners that these value points are guidelines. A student may use their own words, and a correct point still earns its mark. That rule is printed at the top of CBSE's published marking schemes. So the exact wording does not matter. What matters is whether the point is on the page at all.

This is step marking - marks given for each correct step, not just the final answer. It works in your child's favour when the steps are written. It cannot help when they are not.

A step that is not on the page cannot be given a mark, however well your child understood it.

Why did I lose marks in maths when my answer was correct?

Because the answer is only one of the marks. CBSE's Assessment and Evaluation handbook describes two kinds of maths mark. These notes come with a sample maths marking scheme in the handbook, a 2021 guide. They are not a rule printed for every paper, and the scheme for each board paper still decides each mark. Method marks are for a correct method applied to the question. Accuracy marks are for a correct answer or a correct middle step.

The handbook adds a note that surprises families. An accuracy mark cannot be given unless the method mark behind it is earned. A right answer reached by wrong working earns no accuracy mark. A right answer with no working leaves the examiner nothing to give the method marks for.

Writing the formula alone is usually not enough either. The handbook says quoting a formula is "not usually sufficient". The formula should be used on the question, for example by putting in the numbers. A formula copied at the top of an answer and then left is a method not yet shown.

Do you lose all the marks for one wrong step?

No, and this is the part worth knowing. The handbook says method marks are not lost for a slip in the numbers, a slip in the algebra or an error in units. So a child who sets up the question well and slips near the end keeps the marks for the steps that were right.

CBSE's marking schemes add a second protection. An error is to be cut only once, not again for its knock-on effect on the later steps. A wrong number in line two does not cost every line after it.

Is knowing the formulae enough?

Not on the papers we have read. Of the 80 marks on the CBSE Class 10 Mathematics Standard paper of 10 March 2025, only 2 tested recall of a fact or formula. The rest asked a student to use a method or connect ideas. Our reading of that 2025 Maths paper shows the question-by-question working.

That count comes from our own tagging of each question, not from a board figure. But the point holds on its own. Reading a solved example is not the same as writing one on a blank page. The paper pays for the second.

Where else does a known answer lose marks?

In a few places, and each one is a gap between what was known and what was written.

• The question read too fast. A question that asks for two reasons has marks for two. One reason earns what one reason is worth.
• The unit left off. Where the scheme prints the answer with its unit, the unit is part of that value point. How ICSE Physics numericals are marked shows what the examiners there say about units.
• The label not written. Some marks are for the drawing itself. Where the marks go in CBSE Science shows a 2026 diagram question with half a mark on each label.
• The reason not given. Where a question says justify or give a reason, the reason is a value point of its own. Stating the result and stopping leaves it blank.
• The question not reached. An unfinished answer earns only what is on the page. Managing time in the 3-hour paper covers how the paper's time runs out.
• The case read but not used. In a case-based question, the numbers and facts the answer needs are in the passage. An answer that ignores them can miss the point being asked. Case-based and competency questions, explained shows how those are marked.

Does handwriting affect marks in CBSE?

The marking schemes we read give marks to value points, not to neat writing. But an examiner can only give a mark for a point they can read.

CBSE's own handbook names the risk. It lists the "halo effects associated with hand-writing, grammar and spelling" as a problem that marking guides must work against. That is one reason two examiners can reach different marks for one answer. CISCE is plain about it in its 2025 report on the ICSE Physics paper. Its advice to candidates reads: "Keep your handwriting neat and legible."

How can you avoid losing marks in Class 10 boards?

• Write every step, even the obvious one. The written step is the one that can be marked. How to write answers to get full marks shows what that looks like for 2, 3 and 5-mark questions.
• Check the returned pre-board script, not the total. The script shows which value point was missing. The total cannot. Why pre-board marks differ from board marks explains what a school's marking can and cannot tell you.
• Read one answer against the board's scheme. Take a question that got part marks. Put the scheme's value points beside the working. The missing one shows in a few minutes.
• Learn what the scheme rewards at the top. High marks come from the same value points, written every time. How to score 95%: what the marking scheme rewards goes through them.
• Turn the findings into a plan. Sort the marks lost into what needs practice and what needs teaching. Turning a mark-loss report into a 30-day plan shows the sort.

What is not being claimed here?

No count of how often a mark is lost in any of these ways. Nothing on this page counts that, because no script has been counted for it. A figure like that needs a counted set of scripts and a stated method.

The rules above come from CBSE and CISCE documents, named where they are used. The 2 recall marks describe one paper, not every paper. Where anything here differs from a board's own marking scheme for a paper, the board's version wins.

About the author

Deepti Sardana

Founder Member & Academic Lead

An IIT alumna (M.Sc., M.Phil.) with over 25 years in teaching, child psychology and learning assessment. As Academic Lead at EduBrahma, she leads the method TRUtesting uses to find where and why a child loses marks.

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