A course management system or learning management system (CMS/LMS) allows teachers and students to access course materials, submit assignments, and test online. It provides benefits like 24/7 access to materials, the ability to reach different learning styles, and helps students develop 21st century skills. Edmodo is an example of a free CMS that teachers can use to communicate with students, share links and videos, conduct polls and surveys, and give students more control and independence over their learning. While not mandatory, it can be a useful tool for students who want extra practice or who enjoy using technology for learning.