Classes
A class is who a group-scoped event is about. A static class keeps a list you add to; a dynamic class holds whoever's attributes contain its filter, so nobody keeps it up. Beside the classes somebody keeps are temporary lists, picked by a person for one send: you can see them, but a key cannot change one and an event cannot name one. In the High school pack a class is, for example, “5A”.
POSTAdd to a class
Requires groups:write. Up to 500 students or parents — the class's own kind — in one call. Somebody already in it is not an error, so a sync can send its whole list every time. One id this instance has no record of, or one member of staff, refuses the lot before anything is written.
200 with added: how many were new. 400 on a dynamic class, which keeps no list, or for an unknown id or a member of staff, named. 409 on a temporary list.
One result: the same fields in every pack. Press Response on the sample to see one whole.
On failure the body is { error, code } instead.