Experienced teachers know that silence on their part is very effective. They will punctuate their waiting by extending it 5 to 10 seconds after the classroom is completely quiet. Then they begin their lesson using a quieter voice than normal. A soft spoken teacher often has a calmer, quieter classroom than one with a stronger voice. Her students sit still in order to hear what she says.
Uncertainty increases the level of excitement in the classroom.
The technique of direct instruction is to begin each class by telling the students exactly what will be happening. The teacher outlines what he and the students will be doing this period. He may set time limits for some tasks. An effective way to marry this technique with the first one is to include time at the end of the period for students to do activities of their choosing. The teacher is more willing to wait for class attention when he knows there is extra time to meet his goals and objectives.