The ability of changes to capture attention can work to the advantage of the lecturer. If possible, give the students an example of a previous research paper, reaction paper, etc., that exemplifies your expectations. Tell the students what you expect of them. Students will be motivated if they know what your expectations are and how they will be evaluated. Provide concrete examples and illustrations.
Students also like to share their knowledge and experiences which enhance motivation.
Reinforce positive learning behavior. Students need to experience positive reinforcement in the classroom. However, a teacher can also be guilty of using too many positive reinforcers. Negative feedback will automatically result in students closeting their thoughts and opinions. Provide feedback and cues.