Just like in a real classroom, a student can get the teacher's attention by raising their hand. As a result, the teacher will receive a sound notification and see a notification icon informing them a student is asking for assistance. The student may then communicate further with the teacher by sending a message via the public or huddle chat (if enabled).
To raise a hand, students must press the Raise Hand button at the bottom-right of the student canvas screen. A yellow icon indicates the teacher should have received the notification.