Your school administrators and anyone with administrator access (depending on your school setup, they may include guidance counselor and school leaders) can see the messages you send as well as replies and messages sent from students/families.
Your student's may have advisors (possibly Special Education case managers, EL case managers), who may also have access to a particular student's communications.
You also can include teachers as shown below - and they will get your message (and any replies - according to certain criteria).
This access supports transparency in support of facilitating clear communication for all students and families, including those that require translation services.