First you need to make your way to the Manage Pupils page, where you can view and manage the full list of pupils in your Complete Maths account, searching and filtering the table to find the desired pupils. How you get here is dependant on which user permissions you hold on the platform, find out more about user permissions here.
Start by clicking on your name in the top-right of the platform, and selecting either Manage Pupils or School Settings > Manage Pupils depending on what you can see in the menu.
Once on the Manage Pupils page toggle off 'Only Assigned Pupils' in the table filters to show all pupils. Any pupils who haven't been assigned a class in this academic year will appear at the bottom of this list.
Next using the table filters, as well as the search function, find and select the pupil you wish to edit.
Click Edit and you can change any necessary details including your pupils usernames, password etc.
Finally click Update to save any changes you have made.