A teacher asks questions in the class to

A teacher chiefly asks questions to attract and hold the students' attention on the lesson.

Keeping students busy is a trivial aim, not the purpose of questioning.

Maintaining discipline is a by-product, not the main reason for questioning.

Teach is too broad, whereas questioning specifically focuses attention.

Questioning also checks understanding and stimulates thinking.

Well-framed questions are a key tool of the Socratic, dialogic method.