Create a course using separate groups Create two students: studenta and studentb in two different groups (groupa and groupb) Create a teacher: teachera enrolled in the groupa group Create a quiz activity Start and finish quiz attempts with studenta and studentb As admin, enable "Mobile services": Plugins ► Web Services ► Mobile Create a Token for the teachera user: Click on Site administration ► Plugins ► Web services ► Manage tokens Next, you can do a CURL REST call simulating a WS client with the teacher user. You need to replace the wstoken, quizid (with the quiz instance id) and the URL of your moodle instance curl 'http://localhost/m/stable_master/webservice/rest/server.php?moodlewsrestformat=json' --data 'quizid=10&userid=106&wsfunction=mod_quiz_get_quiz_attempts&wstoken=a70d553bbaf6d9b260a9e5c701b3c46e&groupid=0' | python -m "json.tool" Confirm that you receive the attempt information for all the students in both groups (by default the teachers can access to all groups) Now, replace groupid=0 with groupa id and check that you receive only the attempt for the studenta Now, at course level, remove the capability moodle/site:accessallgroups for the teacher and editingteacher role Execute the first curl request (the one with groupid=0) you should see only the studenta attempt If you try to retrieve the attempts for groupid=GROUPB_ID you should see an exception "notingroup"