I have read two posts about journals in the past few weeks: here and here. Journaling really looks different in every classroom. This is my first year using them on a regular basis and it is going very well.
We began the year drawing and using journals as a choice, but recently we have begun to have journal time together. Children are more interested in adding letters to their pages now than they were at the beginning of the year, so we put the alphabet sheets on the table to encourage them.
The journals are a great way to learn about sketching, too. During our forest project, we sketched in the forest, and then revisited those skecthes for another draft.
Yesterday, we all sat down with our journals, and I put on a slideshow of recent photos. I would like the children to use their journals to reflect on what is happening in the classrooms and their interests; but it is in no way an obligation to use those prompts.
There is also no obligation for the children to make an "entry" on one page - many of the younger ones just find any blank page or space in their book and draw. One child seems to be creating four page stories one after another, "reading" them to us when she is finished.
I think there must be more ways to use them, and it really depends on the classroom, the children, the curriculum...