As the school's Flocabulary subscription manager, you cannot directly add or create student accounts.
See this help article on how students can sign up with a class code given to them by their teacher(s).
You can delete a student account if a student has left the school or for any other reason, e.g., at parent request.
1. Go to My School.
2. Select the school you want to manage.
3. Go to Students.
4. Hover over the student you want to delete and click the red remove symbol.
5. Confirm that you want to delete the student and all associated data and information.