Seating To every great assembly, there is a sense of order. This way, each teacher takes responsibility for the appropriate behavior of their students. The introduction is a critical part of the performance. It builds credibility for the speaker and piques the interest of the audience. The introduction should begin only after the audience is seated and the room is quiet.
Most speakers use their introduction to 'set-up' their talk, and prefer it to be read verbatim.
The speaker should not have to dismiss the students. This task, and any other beyond the program itself, should be handled by a teacher or an administrator.