At a glance
- Subject code
- 086
- Board paper
- 80 marks, 3 hours
- Internal assessment
- 20 marks (including 5 for practical work)
- Question mix
- 50% knowledge, 30% application, 20% analysis
- Internal choice
- About 33% of questions
Unit weightings for the 2027 board paper
| Unit | What it covers | Marks |
|---|---|---|
| I Chemical Substances: Nature and Behaviour | Chemical reactions and equations; acids, bases and salts; metals and non-metals; carbon and its compounds | 25 |
| II World of Living | Life processes; control and coordination; reproduction; heredity | 25 |
| III Natural Phenomena | Reflection and refraction, mirror and lens formulae, the human eye, dispersion and scattering | 12 |
| IV Effects of Current | Ohm's law, resistors in series and parallel, heating effect, power, magnetic effects of current | 13 |
| V Natural Resources | Our environment: ecosystems, ozone, waste | 5 |
| Total | 80 |
Source: CBSE Science Class X curriculum 2026-27.
Taught but not in the board exam (2026-27)
CBSE lists these topics as part of the syllabus but assessed only formatively in school. They can appear in internal assessment or the portfolio.
| Unit | Topic assessed in school only |
|---|---|
| I | Periodic Classification of Elements |
| II | Evolution |
| IV | Electric motor, electromagnetic induction, electric generator |
| All | Information in the boxes in the NCERT textbook |
Where Class 10 Science marks are lost
- Balancing and classifying equations: students balance correctly but name the reaction type wrongly (displacement vs double displacement, or missing that a reaction is also a redox reaction).
- Carbon compounds: naming by IUPAC rules and drawing structures of isomers; small slips cost whole marks.
- Ray diagrams: rays without arrows, wrong use of the principal focus, images not labelled real or virtual.
- Sign convention in the mirror and lens formulae: the commonest single source of wrong answers in Unit III.
- Combinations of resistors: calculating the equivalent resistance of mixed circuits, then the current in one branch.
- Biology long answers: describing a process (for example human digestion or double fertilisation) in the wrong order or without the labelled diagram the question asks for.
How one-to-one Class 10 Science lessons work
Lessons are 60 minutes, one to one, in LiveTutor's online classroom with video and a shared whiteboard, where ray diagrams, circuit diagrams and labelled biology diagrams are drawn live and corrected on the spot. Because Science is three subjects in one paper, the first lesson maps where your child is strong and weak across chemistry, biology and physics, and the tutor plans the term around the weakest unit rather than the school's order alone.
Tutors who teach CBSE use NCERT text first, then exemplar problems and CBSE sample papers, because board questions are built on NCERT wording. In the run-up to the boards, lessons work through assertion-reason and case-based questions, where the science is familiar but the reasoning format is not.
When to start
Start in the first term if chemistry equations or physics numericals already feel shaky: Unit I alone is 25 marks and the later chemistry chapters build on equation writing. Starting after the pre-boards is still useful, with lessons focused on high-weight units and on past mistakes. The optional second board exam in May allows a second attempt at Science, but it covers the full syllabus and is best kept as a fallback.
Common questions
Is evolution in the Class 10 board exam?
Not in 2026-27. CBSE lists evolution, the periodic classification chapter, and the motor, electromagnetic induction and generator topics as taught but assessed only in school. Heredity is still in the board syllabus.
How are the 20 internal marks split?
Periodic assessment 5, multiple assessment 5, portfolio 5, and subject enrichment (practical work) 5. A student must get at least 33% separately in the board paper and in internal assessment.
Do we need separate tutors for physics, chemistry and biology?
Usually not. One tutor who teaches CBSE Class 10 Science covers all three units. If one area is far weaker, for example physics numericals, you can ask for a tutor whose strength is that area.
Which practicals should my child know?
The syllabus lists experiments such as finding pH with indicator paper, showing that carbon dioxide is released in respiration, finding the focal length of a concave mirror and convex lens, tracing rays through a glass slab and prism, and studying resistors in series and parallel. Questions on these can appear in the theory paper.
How much does Class 10 Science tutoring cost?
$15 a lesson, the same for every subject and level, on a weekly plan of 1 to 5 lessons billed monthly. The first lesson is a free trial.
Sources
Dates and figures on this page come from these official and published sources. Always confirm deadlines on the official page before acting on them.