Create a course with separate groups forced Create two different users (u1 and u2) and two groups (g1 and g2) Enrol u1 in g1 and g2 Enrol u2 in g1 Crete a editing teacher, ensure the capability access all groups is On for the editing teacher Create a general use forum As u1, create a new discussion in the forum for g1 and another one for g2 As u2, create a new discussion for your only group (g1) Create a Token for the both users: Click on Site administration ► Plugins ► Web services ► Manage tokens Next, you can do a CURL REST call simulating a WS client . You need to replace the wstoken, forumid (the forum instance id) and the URL of your moodle instance. First use the token for u1 curl 'http://localhost/m/stable_master/webservice/rest/server.php?moodlewsrestformat=json' --data 'forumid=13&sortby=timemodified&sortdirection=DESC&page=0&perpage=20&wsfunction=mod_forum_get_forum_discussions_paginated&wstoken=ffbe3a3002f235bf9d01fd9369e10b66&moodlewssettingfilter=true'| python -m "json.tool" Confirm that You see all the messages you posted in both groups, you see the u2 discussion too Execute the same command but using the token for u2 Confirm that You see all the messages you posted in your group (g1) including the one posted by u1