I had several students whom had major problems main ideas. When they wrote their papers, they had a difficult time trying to write topic sentences and even determining what each body paragraph would be about. I found an article and removed the title and subtitles.
They had to read the article and decide an effective title and subtitles.
You can have the students do this in groups or independently. I only had the students whom assessed poorly in idea formation complete this activity. I had all students do a lesson with their greatest weakness. (See also Organization and Sequencing Lesson AND Run-on Lesson.)