On the start page there are started loops. They look different depending on whether you are a teacher in the loop, or a student. A loop where you are a student has a progress bar and a play button, and the ones where you are a teacher have a button that says To Teacher Panel. If you click on a loop where you are a teacher, you will come to the preview mode of the loop. If you click on a loop where you are a student, you will come to work mode where you can communicate through the nodes.