First select a group from the menu on the left, under the tab 'students'. Then click the icon + 'New group'. Enter a name and, if required, a text that the students in the group will see when they view the content. Choose 'yes, results saved (students' progress tracked)' if the student is required to answer all the questions and you wish to monitor the results. Only select 'no' if you want the student to be able to 'browse' though the lessons (like a teacher). In this case no progress or time spent is logged. Click 'add' to create the group. In the table of groups the new group appears as the bottom row.