Click on the assign users icon in the group management tab.
Select the teachers you want to assign to the group.
Group Membership Rules
All users are assigned to the default group. If you do not assign a user to a group they will be sent the default form frequencies.
Once a user is assigned to a group they receive the get the events and form frequencies assigned to that group.
A user can be assigned to unlimited groups in an academic year. However, a user can not be in two groups that are both assigned the same event or form.