So often, students just tell about the large picture of an experience. They get so caught up in listing all of the “moments” of the experience that they forget to really hone in on each part of it with vivid details for their readers. This is why one of my favorite writing strategies to teach is “explode the moment” writing.
The first time I teach “explode the moment” writing, I go over an anchor chart that breaks down what this strategy entails. The anchor chart also includes a model as a clear example. 
I stress the importance of using descriptive word choice and sensory images. Using the example, we go through picking out sensory details the author used. We also mark strong, descriptive word choice that helps us paint a picture in our minds. While marking the text, I like to make a T chart. We also record the strong sensory images on one side and strong word choice on the other side.
Then, I give students a pretty narrow topic/prompt. I might ask them to explode a moment from their first day of school, a special event at school (field trip, class party…), etc. After they are comfortable with narrower topics, I make it a little higher-level thinking. For example, I have students explode a moment they felt a certain way (i.e.”A time I felt lucky”). I first give students a graphic organizer to fill in the setting, characters, what happened, feelings/emotions, thoughts, and sensory details from their moment. They use this graphic organizer below to create their rough draft that makes the “explosion” visual for them.
Lastly, students write their final copies onto pre-made “explosion” templates. I find that students really like sharing and reading each other’s moments, so I make a bulletin board of these final copies to have on display.
All of the resources pictured in this blog post can also be found in this Explode the Moment Pack:
Do you teach opinion writing with your elementary students? Read this blog post on How I Teach Opinion Writing in the Primary Grades (1-3).