You can easily export a class roster that includes the email addresses for your students from Infinite Campus. You can then use those email addresses in various apps like Doctopus or to create a Google Group to send out class emails so you only have to type in one email instead of all of the emails. Creating a Group in Google Apps is an easy way to quickly communicate and share with a group of people or even a whole class.  Once the group is setup, you can easily send emails to everyone in the group or share with them in any of the Google Apps.