Publishing in a catalog means that you make drills available in a private environment in which participants can choose which drills they want to take. This is mainly used within educational institutions. In this way, learners can work ahead or work with extra information that is not mandatory. If you still want to follow the progress of the participants, you need to add the drills in a group and link the participant to it.
Participants do not automatically have access to this content, they have to be invited.