How do I add a grop to a group?

Question

Need a group for each class so mails for that class remain within that class. Then need to include each class group into a school group so mail to school group is received by all class groups. etc

Answer 1

I don't see how you could have several classes of members, some getting some emails and some getting others. The only choices are that the member can get all emails, get a summary, or not get emails.

You could make up different yahoo groups for each different school group.