A teacher is teaching children by demonstration of a task to correct the performances of an already learned task. He is using _____ method of teaching.

Modelling is a teaching method where the teacher demonstrates a task or behavior for students to observe and learn from. When a teacher demonstrates a task to correct the performance of an already learned task, they are using the modelling method. This approach is based on Albert Bandura's Social Learning Theory, which emphasizes learning through observation and imitation of models. Modelling is particularly effective for teaching complex skills and correcting errors.