Here are some directions for setting up an e-mail group. There is also a helpful picture attached to this entry.  
 
(1) Open Address Book, which is on your dock at the bottom of the screen. 
 
(2) Under the Group column, click on the plus sign in the lower left-hand corner. You can label the group Parents. 
 
(3) Under the Name column, click on the plus sign in the lower left-hand corner. Place a name and e-mail address in the appropriate fields. The field for an e-mail address is next to the word Work. 
 
(4) Continue to add group members by clicking on the plus sign in the lower left-hand corner of the Name column.