In Jolly Classroom, every school has an admin that is in charge of the school settings like the school name, country and billing details.
If you are an individual using Jolly Classroom, that person is probably you. If you are part of a school, that person can be a teacher, a head teacher or a school administrative person.
To change those details, the current admin of the school should head over to "School" under the "Settings" sub-menu on the left side:
and on the menu, click on the "Edit" button:
You will see a floating window and you can click on the dropdown to select the new teacher with the School Admin role.
After clicking save, the new user will be able to change school settings and you will be redirected to the home page.