The main idea is what something is mostly about. Main ideas are typically found in a literary passage. Central ideas are found in an informational text. The theme is the lesson or message that the writer wants to get across in his or her story.
central idea: refers to what the text is mainly about. this is not the topic of the text. can most likely be stated in one sentence.
theme: the life lesson, authors message, or moral of the story. you have to make an inference to determine the theme, it is not given to you. a story can have multiple themes. theme is not the same as topic or central idea.
