My 5th Grade students had to complete a science research writing prompt last year. The hardest part of this process was not the actual writing, it was more of the research and planning. Two tools that I believe helped my students the most were Alpha Boxes and Prompt Plans.
I use Alpha Boxes in both my teaching of reading and writing. During Guided Reading, I have my small groups keep an alpha box for each book that they read. The students record the book title or topic in the middle of the alpha box. As we progress through the book, the students add 5 vocabulary words each day that I have pulled from their text. These are are key vocabulary that we discuss and use context clues to decipher the meaning of. Students then can add more important words to their alpha boxes as they read independently. Not only is this a great tool to keep the students refreshed on their vocabulary, but it also is a running record of the key words from each book.
In the writing process, alpha boxes can come in hand when the students are researching. Instead of jotting down pages of notes in their writing notebooks, I often have students write down key words that they find in their research on alpha boxes. This tool is great when students are beginning their rough drafts so that they have a "thesaurus" so to say of the key words that they need to use in their own writing.
This planning graphic organizer is another helpful tool for students in the pre-writing process. It is especially helpful when there is a specific prompt given to students for a writing test.