Explain to children that paragraphs usually contain several sentences. Introduce the idea of a topic sentence by explaining how it conveys the main idea of the paragraph and explains what the paragraph is about. Use the chalkboard to provide an example of a paragraph with a strong topic sentence.
Tell your students that the topic sentence is often, but not always, the first sentence in the paragraph. Reinforce the idea that it may assume other positions in the paragraph as well.
Distribute a worksheet with several paragraphs on it to each student in your class. Ask your students to use a colored pencil to underline the topic sentence in each paragraph. Go through several examples with them until they master locating topic sentences.
Pass out a worksheet with five sentences on it, all on separate lines and in random order. Have your students cut the sentences into separate strips. Ask them to rearrange the sentences into a paragraph that makes sense, placing the topic sentence in the first position.
Ask your students to write a five-sentence paragraph about their favorite pet. Ask them to make the first sentence the topic sentence. Explain that every sentence in the paragraph must relate to the topic sentence.
Assign homework that involves creating topic sentences. Grade it to ensure that each student has mastered writing topic sentences when working alone at home, as well as in the classroom setting.