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STUDENT GUIDE · CBSE

CBSE practical exams Class 10 and 12

How practical and internal marks are split, who examines you, and how to prepare for the viva.

IN SHORT

In Class XII, Physics, Chemistry, Biology, Computer Science and Physical Education carry 30 practical marks out of 100, examined by an external examiner CBSE appoints, usually in January and February before the theory papers. Commerce subjects, English and Mathematics carry 20 marks for projects or internal assessment. In Class X, every main subject has 20 internal-assessment marks, given by the school. Check each subject's current CBSE curriculum for the exact split.

Updated · Mayo International School, Patparganj, East Delhi

XII science practical
30 marks
XII project subjects
20 marks
X internal assessment
20 marks
XII examiner
External, CBSE-appointed

Class XII marks split (theory + practical/project)

Physics, Chemistry, Biology70 + 30
Computer Science, Informatics Practices70 + 30
Physical Education70 + 30
Mathematics80 + 20
Accountancy, Business Studies, Economics80 + 20
English80 + 20

What the practical exam includes

  • An experiment (or program, for Computer Science) done on the day
  • Your lab record or practical file
  • A project or investigatory project
  • A viva: short questions on your experiments and project

Preparing for the viva

  • For every experiment, know the aim, the principle, the precautions and the sources of error
  • Practise taking readings and writing units correctly
  • Make sure your record is complete, neat and signed
  • Know your project well enough to explain it in two minutes — it must be your own work
  • If you don't know an answer, say so and explain what you do know

At Mayo

Lab records are checked every week, not the night before the practical. Classes X and XII sit two full pre-board rounds under board conditions.

Questions parents ask

How many marks are practicals in CBSE Class 12 Physics?

30 out of 100, with 70 for the theory paper.

Who conducts CBSE Class 12 practicals?

An external examiner appointed by CBSE, together with an internal examiner from the school.

When are CBSE practical exams held?

Usually in January and February, before the theory papers. CBSE announces the dates each year.

What is asked in a practical viva?

Questions on the aim, principle, precautions and errors of your experiments, and on your project.

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Sources

Rules change each year: check the official notice for your year. Mayo's own figures come from the school's records.

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