My principal encourages all teachers to have students do class presentations during the year. I like the idea, but the thought of listening to 150 “oral reports” on a chemistry topic is mind-boggling, not to mention time-consuming. Do you have any suggestions for making this a positive experience for both the presenters and the audience (and the teacher)?
I’m assuming your principal wants students to develop and demonstrate skills that will be useful regardless of what they do after high school, such as presenting to an audience.
From experience, I know exactly what you mean about implementing this. There are only so many “oral reports” or PowerPoints on endangered species, elements of the Periodic Table, infectious diseases, or famous physicists you can sit through at one time. The students in the audience will get restless, too. With 5-6 classes of 25-30 students each, even if each presentation took 5 minutes, you would have to devote several class periods to this task, including time for research and preparation. And quite frankly, I’m not sure the benefits would justify the time and effort for a once-and-done report, for the presenter or the audience. So perhaps it’s time to think outside of the box:

• No law says all students must deliver their presentations at the same time. What would happen if you spread out the opportunities rather than try to fit everyone into a few class periods, one after the other?
• Is it essential for all students report on the same theme or topic or use the same template?
• Think about presentations you’ve attended. What made them effective? Was it a team effort, such as a panel discussion? How did the presenters use visuals or other media? How did they engage the audience?

One authentic practice scientists do is communicate the results of their research. You could have students emulate this practice, without adding additional activities to your crowded schedule.

For example, after a lab investigation, you as the teacher probably go over and discuss the results. Instead of your discussion, you could assign a team of students to present their results in a panel format. Choose one team at the beginning of the lesson to be the “presenter.” You could assign roles to the team members so that each would participate: Person 1 – Introduce the team and present the question, problem, or hypothesis. Person 2 – Summarize the procedure.  Person 3 – Provide a display or description of the data, observations, or results. Person 1 (again) – Relate the results back to the question or hypothesis. Person 4 – Note any questions the team had, how the investigation could or should be done differently, and moderate questions from the audience. Give the team some time at the end of the activity or at the beginning of the next class to prepare their presentation. Rotate the roles so students do a different report component each time the team presents. Students could incorporate available technology, such as an interactive white board, digital camera, or document projector.
At first, you may have to model how to summarize and how to make an effective presentation (my students enjoyed it when I modeled an ineffective one, too). You may also have to model how to contribute as a respectful audience member and suggest types of questions and prompts for discussion: Compare their results to yours. How are they similar? Different? Use the rubric you already have for investigations to provide feedback to the team. The audience could match the presentation to the rubric and note any differences in their outcomes.
Once your students have experience with this type of presentation, invite your principal to be part of an audience to see what your students are capable of doing.
 
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