When you have started a loop, you can edit it by clicking Edit loop, just below the name of the loop. That means you can shape for example methods and content together with the group of students who are in the loop and add or remove material so that it suits that particular group. You can start editing the loop before you have made it active for your students. Note that the original loop will not be affected by your changes to the started loop. The started loop is a copy of the original and they are not linked in a way that makes the content move between the loops. That, in turn, means that if you want to keep your version of the loop to hand out to a new group of students, you must save the latest version back to My loops, by clicking Copy loop.