CBSE Class 10 Study Guide

The CBSE Class 10 board exam (officially the Secondary School Examination) is set and run by the Central Board of Secondary Education. CBSE says its schools number nearly 32,000 across India and 26 countries. The exam covers the entire Class 10 syllabus in each subject; Class 9 is examined by your school, not by the Board.

Your subjects

For the 2027 board exams, the CBSE scheme of studies has five compulsory subjects with a board exam:

1. Language 1 (for example English Language and Literature, or Hindi Course A)
2. Language 2
3. Mathematics, at Standard (041) or Basic (241) level
4. Science (086)
5. Social Science (087)

On top of these you can add optional subjects, such as a skill subject, up to a maximum of 7 board subjects in 2027 (5 compulsory + 2 optional). Health and Physical Education, Work Experience (now part of HPE) and Art Education are assessed by your school. If you fail one of Science, Mathematics or Social Science but pass an optional sixth subject, CBSE replaces the failed subject with the optional one when it works out your result, as long as you have cleared your languages.

The 80 + 20 split

Each main subject is out of 100: 80 marks for the 3-hour board paper and 20 marks of internal assessment done at school. You must appear in and complete both parts. CBSE's 2026-27 curriculum puts the pass rule this way: a student must secure "a minimum of 33% marks separately in external and internal assessments, calculated on the combined total of Internal Assessment and External Examination marks".

Two board exams from 2026

CBSE introduced two board examinations for Class 10 from 2026, in line with NEP 2020. CBSE's list-of-candidates circular for 2027 (17 September 2026) confirms the policy continues: the first board exam, held in February to March, is mandatory for every Class 10 candidate, and the list for the second exam is filled only after the first one is over. In 2026 the main exam ran from 17 February to 11 March and the second exam from 15 to 21 May.

CBSE's February 2026 notification on the scheme says:

• Passed and eligible students may improve their performance in up to three subjects out of Science, Mathematics, Social Science and the languages.
• A student who misses three or more subjects in the first exam cannot sit the second. They are placed in the "Essential Repeat" category and take the main exam the following February.
• Students placed in Compartment after the first exam sit the second exam under the Compartment category.
• No additional subject may be added after passing Class 10.

For regular students, CBSE takes the better of the two performances when it prepares the final result. CBSE's July 2026 press release reports that of the students who sat the 2026 second exam to improve, 59.95% improved on their main-exam performance, and that the overall pass percentage after combining both exams was 96.78%.

How grades are given

Marks are shown with a grade on a 9-point scale. Grades are positional, not fixed bands: CBSE ranks all students who passed a subject and gives A-1 to the top eighth, A-2 to the next eighth, and so on through B-1, B-2, C-1, C-2, D-1 and D-2. E means Essential Repeat. This method is used where more than 500 candidates pass the subject.

Standard or Basic

Class 10 Mathematics is offered at two levels, Standard (041) and Basic (241), written on the same day. Both follow the same 2026-27 Class 10 syllabus and the same paper layout, but the Basic paper leans more on recall and understanding (75% of marks against 54% in Standard). CBSE is discontinuing the Basic and Standard split from 2026-27 for the new Class 9, but its curriculum states that students in Class 10 in 2026-27 continue under the existing scheme and may opt for Mathematics Basic. The optional Mathematics Advanced and Science Advanced papers only reach the Class 10 board exam in 2027-28, so they do not apply to the 2027 exam.

Unit weights (80 marks)

• Algebra: 20 (polynomials, pair of linear equations in two variables, quadratic equations, arithmetic progressions)
• Geometry: 15 (triangles and similarity, circles and tangents)
• Trigonometry: 12 (ratios, identities, heights and distances)
• Statistics and Probability: 11
• Mensuration: 10 (areas related to circles, surface areas and volumes)
• Number Systems: 6 (real numbers)
• Coordinate Geometry: 6 (distance and section formulae)

The paper, section by section

The 2026-27 sample paper, which CBSE says has no change in design from last year, has 38 compulsory questions in five sections:

• Section A (20 marks): 18 MCQs and 2 Assertion-Reason questions, 1 mark each.
• Section B (10 marks): 5 very short answer questions of 2 marks.
• Section C (18 marks): 6 short answer questions of 3 marks.
• Section D (20 marks): 4 long answer questions of 5 marks.
• Section E (12 marks): 3 case-study questions of 4 marks, split into sub-parts.

There is no overall choice, but there are internal choices in 2 questions each of Sections B, C and D, and in the 2-mark sub-parts of Section E. Calculators are not allowed, and you take π = 22/7 unless told otherwise.

Limits written into the syllabus

• Heights and distances: no more than two right triangles, and angles of elevation or depression of only 30°, 45° and 60°.
• Area of a segment of a circle: central angles of 60°, 90° and 120° only.
• Surface areas and volumes: combinations of any two of cubes, cuboids, spheres, hemispheres and right circular cylinders or cones.
• Quadratic equations: real roots only, by factorisation and the quadratic formula, plus the discriminant and nature of roots.
• Statistics: mean, median and mode of grouped data, with bimodal cases avoided. The mean can be asked by the direct, assumed mean or step deviation method.
• Proofs to know: irrationality of √2, √3, √5 (and numbers like 3 + 2√5), the Basic Proportionality Theorem, and the two tangent theorems (tangent perpendicular to radius; tangents from an external point are equal). The other similarity criteria are stated without proof.

Internal assessment (20 marks)

Pen and paper test and multiple assessment 10 marks (5 + 5), portfolio 5 marks, lab practical 5 marks.

Unit weights (80 marks)

• Unit I, Chemical Substances: Nature and Behaviour: 25 (chemical reactions and equations, acids, bases and salts, metals and non-metals, carbon and its compounds)
• Unit II, World of Living: 25 (life processes, control and coordination, reproduction, heredity)
• Unit III, Natural Phenomena: 12 (light: mirrors, refraction, lenses, the human eye, prism, dispersion and scattering)
• Unit IV, Effects of Current: 13 (electricity, magnetic effects of current)
• Unit V, Natural Resources: 5 (our environment)

Three sections, three subjects

The Science paper is split into Section A: Biology, Section B: Chemistry and Section C: Physics. The 2026-27 sample paper has 39 questions, all compulsory, with internal choice in some; the question types are objective and Assertion-Reason questions, short and long answers, and source-based or case-based questions. Adding up its marks gives about 30 for Biology, 25 for Chemistry and 25 for Physics, which matches the unit weights above.

For the 2026 exams, CBSE told schools that students must divide the answer book into three sections and write each answer only in the space for its own section. Answers written in the wrong section "will not be evaluated and no marks will be awarded". The 2026-27 sample paper keeps the same three-section layout, so expect the same rule.

What the board paper does not test

The 2026-27 syllabus says these topics are taught but assessed only formatively (at school), not in the board paper:

• Periodic Classification of Elements
• Evolution (acquired and inherited traits, speciation, fossils, human evolution)
• Electric motor, electromagnetic induction and the electric generator

It also says the information in the boxes of the NCERT textbook is not assessed in the year-end exam, and that the colour of the sun at sunrise and sunset is excluded from scattering of light.

How the marks are pitched

The question paper design is 50% knowledge and understanding, 30% application and 20% analysing, evaluating and creating, with internal choice in roughly 33% of the paper. CBSE's curriculum says that about half of board questions across subjects are competency-focused: case-based, source-based, data interpretation and application questions.

Internal assessment (20 marks)

Periodic assessment 5, multiple assessment 5, portfolio 5 and practical work 5. The practical list includes finding pH with indicator, classifying reactions, the reactivity of Zn, Fe, Cu and Al, V-I graphs for a resistor, resistors in series and parallel, stomata, focal length of a concave mirror and convex lens, and tracing rays through a glass slab and a prism.

When the exams are

As of 30 October 2026, CBSE has not yet published the 2027 date sheet; dates are announced by CBSE on cbse.gov.in. CBSE's 2027 list-of-candidates circular says the first board exam is held during February to March. For reference, the revised 2026 Class 10 date sheet (31 December 2025) ran from 17 February to 11 March 2026, with papers from 10:30 am to 1:30 pm. In 2026, Mathematics Standard and Basic were on 17 February, English on 21 February and Science on 25 February. The second board exam in 2026 ran from 15 to 21 May.

1. Start with the official sample papers

CBSE publishes a sample question paper and marking scheme for every subject on cbseacademic.nic.in. The 2026-27 papers came out on 21 September 2026, and CBSE's notification says there is no change in the question paper design or assessment pattern and that the passing criteria stay the same as in 2025-26. The sample paper is the exact layout you will face.

2. Then the real papers

CBSE's Previous Years' Question Papers page has the 2026 main papers and the 2026 second board exam papers for Mathematics, Science and Social Science, and earlier years.

3. Mark with the marking scheme

The marking scheme shows how marks are split inside a question. Mark your own practice strictly against it: if your answer skips a step that carries a mark, you lose it in the board exam too.

4. Time yourself

An 80-mark paper in 180 minutes is a little over 2 minutes per mark. Practise full papers in one 3-hour sitting, and keep 10 to 15 minutes at the end to check.