It is possible to take back or hide answers and feedback after they are mistakenly released to a student.
This can be done for individual students and whole classes.
Take back an individual student's feedback and answers
Click into the student's worksheet from the Markbook. Scroll to the bottom of the page and click Require resubmission. This will hide the answers from the student and allow them to continue working. Feedback will still be visible.
The page will refresh and reveal the Collect work button where the resubmission button was previously. Click this button to prevent the student from working on the lesson. Feedback and answers will both be hidden if the lesson is assessed.
Take back answers from a whole class
Use the Class controls in the Markbook to collect the work or request resubmission from the entire cohort.
The teacher can also hide the lesson from the class via the Lessons page if marking is complete and other classes are still working on the lesson.