Invented spelling is an important stage of students learning to read and write. It builds confidence in the process as the teacher supports them through the process to conventional spelling. Students learn they can write stories and share them with others. Many go on to enjoy writing small books for friends and family. It is important to not be critical with students at this stage, but to encourage them to write as much as possible.
Students can write about a recent vacation they have enjoyed, what they want for gifts, their favorite toy, what they do with their friends, and so on. Most students enjoy drawing in their books, so providing them with paper that is lined on the bottom half and has space for drawing on the top half is recommended. When they are done with writing their book, the pages can be stapled together. Have the student read their stories to you more than once. It is their time to shine and to show off how good they have become at becoming authors.