What I love about this site (the only thing I really used it for) is the daily journal writing prompts. They are age appropriate and break down the monotony by having students write paragraph, sentence, or single-word answers depending on the prompt.
Written by two of the leading researchers on writing for students with learning disabilities, this book provides excellent strategies teachers and parents can use.
Written by a teacher for teachers. Mr. Gallagher does a great job with examples and activities that help students become better writers.
Written by a literacy expert, this is another text that provides teachers not only with various strategies to improve writing, but how to make them work for students with and without disabilities.