Whether you are running for class president or taking a public speaking class, you are likely to have to give a speech sometime during high school. In a persuasive speech, you take a clear, specific position on an issue, then present a call for the audience to take action or accept the position. Establishing credibility, relating to audiences and using public speaking techniques like eye contact and gestures can help you write and deliver an effective persuasive speech.
Choosing a Topic
According to the James I. O'Neill High School website, a good topic is one that takes on issues "controversial and presently open for debate." To come up with a topic, you might brainstorm issues that affect your life or that you've personally dealt with. For example, if a relative has struggled with medical expenses after an illness, you might choose to talk about solutions to health care problems. You might also think about issues that relate specifically to high school students, such as mandatory school uniforms, sex education in public schools or incidences of school violence.
A persuasive speech's introduction does two things. First, it creatively grabs the audience's attention by making them curious about the topic. The University of North Carolina School of Education suggests a number of techniques to hook the audience, including asking a question, using a quotation or making an analogy. The introduction also clearly states the speaker's position on the issue in one sentence. For example, the position statement for a speech about school uniforms might be, "Uniforms should be required in high school because they help prevent social hierarchies and promote a more focused learning environment."
Evidence and Credibility
In order for a speech to be most persuasive, audiences need to be able to trust the speaker to give them credible, factual information. One way to convincingly develop the body of your speech is using solid information from reliable sources. Your main points can be illustrated using a variety of resources, such as websites, scholarly journals, documentaries and government reports. Listing your sources in a works cited page and distributing it as a handout can also give audiences a chance to look up your information on their own.
Relating to Audiences
A persuasive speech is ultimately about convincing the audience that your position is worth considering. Public speaking expert Michelle Mazur writes that simply using the word "you" to address the audience can give them a direct stake in the topic by motivating them to take action or change their thinking. You can also relate to audiences through the use of emotional appeal. For example, if you are persuading them that schools need better counseling programs to prevent bullying, you might share an anecdote from your research about how a particular student was harmed by bullying and how counseling might have helped.
The conclusion is your opportunity to reinforce your argument by reviewing your major points. To be most effective, though, the conclusion shouldn't stop there. Ending with a call to action urges listeners to continue thinking about your speech after it's over. For example, the conclusion of a speech about school uniforms might end by urging audiences to weigh freedom of expression against the benefits of a better learning environment.
Being aware of how your voice sounds can help you make adjustments to enhance your message. Speaking slowly and clearly at a moderate volume will make it easier for audiences to hear and understand your message; speaking too fast, loud or soft will either distract the audience or make it harder to receive your message. The message's persuasiveness can also be enhanced by varying your pitch, tone of voice and emphasis on different words. Varying the sound of your voice can communicate your enthusiasm for your position, keep the audience's attention and help people relate to your ideas.
Your posture, gestures and eye contact all help to make an audience more receptive to your message. According to Oklahoma Panhandle University, a straight, balanced posture conveys that the speaker is knowledgeable and confident. Smooth, well placed gestures can also be used to reinforce specific ideas, while random gestures or unconscious habits, like fidgeting, shifting your feet or playing with hair or clothing can distract listeners. Varying your eye contact across different parts of the room and keeping your focus on the audience can also make you appear more confident and interested.