Ok, back to the point. We discussed this issue with Dr Diana Hicks while attending her lessons in Cheltenham, and she gave us a very sensible answer: students in the class get bored because they feel they've nothing to do. They are not sure what they should be listening for and they are not given any active role in this phase of learning.
So she suggested we turn to peer assessment of presentations. The key of success, in fact, is transforming the passive audience into an active participant in the lesson. And here's her battle-plan:
Student 1: Content
was there any new information?
which information was new to the listener and which was old?
did the visuals help or hinder the information?
would other images/graphs/etc. have been better?
How did the visuals match the speech?
Student 3: Structure and organization
Did the presentation follow a logical sequence?
Did the examples help to clarify the content, or did they generate confusion?
Student 4: Language (grammar, vocabulary, personal style)
Was the language clear?
Did errors hinder communication?
Was the language appropriate? was it too informal or too formal?
Was there a correct use of specific vocabulary?
Student 5: Aims - consistent, coherent, cohesive?
Did the speaker present the purpose and objectives of the presentation at the beginning?
Were they clear?
Did he/she achieve them?
2) of course, all the students have to listen to the presentation
3) each student grades his/her part of the presentation in a scale 1-5 (choose the scale depending on how marks are given in your school system). In this case, 1 is unsatisfactory and 5 is excellent
4) all same number students gather and compare their grades with those of the others. They discuss, share opinions and eventually agree on a common mark
5) students return to their groups and inform the others
6) feedback is given to the presenters.
As for this one, try it with your class and have fun. After all, a student presentation doesn't have to be sleeping time for the rest of the class!