"It is by sitting down to write every morning that one becomes a writer."
Writing prompts are a great way to get students writing on a variety of topics on a daily basis. This website was created by a teacher to share writing prompts and inspirations that he has come across over the past few years. There are about 200 hundred writing prompts if you go all the way back to the beginning. These prompts would work for a variety of grades and could easily be adapted to a variety of situations.
Here are a few that I enjoy:
Maybe consider using a video instead. Here is one that could inspire some writing: