When writing stories, general descriptions don't give a clear picture. Great fourth grade authors use specific descriptions, feelings, thoughts, and the five senses to "paint a picture" for the reader.
Check out these two examples. What a difference!
Revision: I looked around my messy room. Dirty clothes were thrown on the floor. Potato chips crunched under my feet as I walked across the room. My bed was covered with papers and school assignments. I wrinkled my nose at the smell of souring milk from the cup that sat on my bedside table.