CBSE practicals carry 20 marks (Maths, English) to 30 marks (Physics, Chemistry, Biology). Most students treat them as secondary to theory — and consistently leave marks on the table.
Practical Marks Breakdown (Science Subjects)
| Component | Marks | How Evaluated |
|---|---|---|
| Experiment performance | 8 | Observation accuracy, procedure, result |
| Practical file/record | 7 | All experiments neatly written, signed by teacher |
| Viva voce | 5 | Questions on the performed experiment |
| Project | 5 | Presentation, content, understanding during viva |
The Practical File: Non-Negotiables
- Every experiment must be completed and signed by your teacher
- Aim, Materials required, Procedure, Observations, Result — all 5 sections for every experiment
- Neat diagrams in pencil
- Observations filled with actual data — not copied from others
On the Day: Experiment Performance
- Read the assigned experiment fully before starting
- Set up apparatus carefully — examiner watches your setup process
- Record observations as you perform — do not reconstruct at the end
- If an experiment goes wrong, tell the examiner calmly — partial marks given for correct procedure
Viva Preparation: Questions That Always Come
- What is the aim of this experiment?
- What is the principle behind it?
- Name the chemicals/materials used and their role
- What are the sources of error?
Tip
Prepare a viva question list for each experiment. Practise answering out loud. Confident, brief answers score more than long, uncertain ones.