Teachers can control when students review an assignment when they create the assignment. In the Release for Review section they can choose On Submission or By Teacher. If teachers want students to be able to review their assignment as soon as they submit it, they should leave the default selection of On Submission. If teachers want to control when students can review, they should select By Teacher.
Once teachers are ready to release the assignment for review, they can click on the report icon on the assignment page.