After you change your password you will have to update it your iOS device (if you have it connected).
If you click into your mail app after you change your password, your device will automatically prompt you to put in the correct one.
Type in the correct password and press OK.
If you are still prompted to put in your password after this step the password you entered might not be correct, re-enter and try again.
If it still doesn't work follow the instrucitons in the next section: Manually update password.
Manually update password
Go to Settings
Your Settings icon might be in a different place.
Go to Mail, Contact, Calendars
Select your School Email account.
Note: You may have named it something else.
Select the password field and type in your new password.
Click Done when finished.