The schools registered with School Loop generally archive data pertaining to the given school year at the end of the academic year. Here is a brief overview about Year-to-Year Archiving.
LoopMail: LoopMail messages for the three previous school years are available through the Historical Archive link on the left side of your LoopMail inbox.
Archived messages are sorted by school year and you will have access to both your inbox and your sent LoopMail messages. Messages that you have placed in custom folders will not be automatically archived and will remain in their folders. Refer to this link for further details on yearly archived content.