We can send personal messages or we can send messages to the whole school or the entire district depending what address we use to send our message. Many sites invite people of similar interests to join a mailring sponsored by that site. After joining, one will start receiving email addressed to the whole group of people. You might receive one digest every few days, or 3-4 in a day. The digests are especially handy for groups where you prefer to read more than respond.
Many websites offer mailrings.
For teachers some of the best options are found at teachers.net. Following the link will take you to a page where you can subscribe to several mailrings at one time, depending on your interests. If you are on a good, active mailring, you will soon have tons of good ideas, or recipes or other bits of information you want to save. In order to keep from filling up your email screen with these gems, you should create some folders . Go back to your emails and select one that will go in your new topic.