When I teach students how to revise essays, I use color coding to show how the main idea must be repeated in the body paragraphs and in the conclusion. On computer-shared documents, I swipe the main idea in one color, say pink, and supporting ideas in different colors throughout the writing.
I ask students to look for the main idea in the introduction and in each body paragraph. If it is there, we swipe it pink. If it no pink appears in a given paragraph, that tells the student she needs to insert the main idea somewhere in that paragraph. If a supporting idea is stated in a body paragraph, and it is swiped in blue, for example, we look for a blue swipe in the introduction. If it is not there, we insert it. We look for a pink swipe in the conclusion, and a rainbow of other colors corresponding to the supporting ideas used in the body.
Let me show you an example a sixth grade student wrote this week.