It is my understanding that when you sign onto a computer or wireless internet connected to the school, all the data (name, email address, password) from your session gets stored some where and the school can see it. I may be wrong about this.
Yes, you are wrong about the password part. Email sites use encryption on passwords. The only way to get the password is with a key logger. What is not encrypted and can be saved on a network server is the email itself. It is saved as a web page on the server. The email can also be stored as a temp file on the computer used to access the internet.
are they protected because they would be the electronic communications service provider?
They own it, they can pretty much do what they want. Especially if they suspect a violation of policies or rules or breaking of the law. As a private entity, a search warrant is not required.
my first reaction is no because gmail or yahoo would be the service provider.
What is your definition of a service provider? A service provider is one that provides the portal to the internet. Google and Yahoo provide web based email service, which is consider to be the least secure method of sending emails.
The thing to remember, if you are going to access web based emails through a public or network based computer, the email itself can be accessed by the provider of the internet service. They don't need to and have no reason to access the actual email account. If you want to break the rules, use a secure or encrypted email account or use a computer not hooked up to the school's internet portal.
