The School Administrator can 'enable' or 'disable' student management to teachers using the provided toggle button. Access is via the 'License' link on the left of the admin dashboard (see below).
If enabled, teachers can manage any students that they have added to a class in their account. Managing them in this context means changing their passwords and nicknames, and deleting their accounts. If disabled, only the School Administrator can perform these functions. The option is, by default, set as disabled.