1.Firstly because no labortary, Apparatus aids are required

2. Secondly a single Teacher can teach any number of Students at a time.

3. Thirdly it saves much time and lengthy syllabus can be very easily covered in a limited time.

1. The method is against the principal of learning by doing and does not encourage the habit of independent thinking.

2. It lays too much stress on memory work which is just to burden the mind of the pupils which is against the principle of teaching science.