As an Admin, you can update several items about the account for a parent.
First, search for the student within the Applicant Index. Next, click to view their student profile. You will see an account settings ribbon at the top of the profile.
You will be able to edit the following by clicking the edit button for Account Language:
If an account has more than one student, you only need to update the account information once. All students profiles linked to the family account will also update.