After providing a clear explanation of what a topic sentence is, teachers can choose from a variety of age-appropriate activities that teach students to identify and create effective topic sentences. Teachers should explain to students that writing strong topic sentences will help them stay focused on their topics.

Explaining Topic Sentences

After defining the term “topic sentence,” transition to using examples of paragraphs with clear topic sentences. Give students a handout with the paragraphs and read them aloud. For lower grade levels, use paragraphs that have about four or five sentences. After reading the paragraph, ask students if they can identify the topic sentence. Explain how to identify supporting details and how they relate to the topic sentence. To help students understand the differences between topic sentences and supporting sentences, draw a comparison to something familiar. Teacher Kathryn Reilly compares topic sentences to music conductors; they direct all the sentences in front of them. The supporting sentences are like the musicians, who work together to create a cohesive song.

Identifying Sentences in Groups

Have students work in groups to solidify their understanding of topic sentences. Give students in upper elementary grades a handout with simple paragraphs. Instruct groups to underline the topic sentences in red and the supporting paragraphs in yellow. Remind groups that there should only be one sentence underlined in red per paragraph. Give students in middle or high school an envelope with four sentences, each on its own strip of paper. In groups, have them organize the sentences in a logical order, beginning with the topic sentence. Ask them to highlight the strip that is the topic sentence. You can also give middle and high school students an envelope with three to five supporting sentences written on the outside, and a card with the topic sentence inside. They must create a topic sentence for those detail sentences and write it down; then they can check the card on the inside to see how close they came.

Creating Topic Sentences

Now that students can identify topic sentences, have them write topic sentences and paragraphs on their own. Give upper elementary and middle school students a topic, such as “pets” and instruct them to write a detailed yet not too specific topic sentence, such as, “My dog Charlie is a loving and loyal pet.” The supporting sentences should explain how or why Charlie is loving and loyal. You can give elementary students a handout with a paragraph template with space for a topic sentence and three supporting sentences. Have students read their paragraphs aloud to the class, and ask fellow students to identify the topic sentence. You can give high school students a paragraph without a topic sentence or with a poorly written topic sentence, and instruct them to create one or make the current one better.

Writing Better Sentences

Once students grasp the idea of topic sentences, further their understanding by helping them to create better sentences and to think critically about their writing; these skills are particularly important for high school students preparing for college or standardized tests. For elementary or middle school students, read simple paragraphs with poorly constructed topic sentences, such as ones that assume the reader already knows about the subject, paragraphs that start with details rather than a main idea or sentences that don’t grab a reader’s interest. Work together to write a sentence that is more intriguing. For example, turn the sentence “Music is fun” into “I love listening to music because it relaxes me and makes me think about important things.” Challenge high school students to write a simple essay about a favorite topic. Have them write a thesis statement first, followed by three topic sentences that will serve as the first sentences of three body paragraphs.