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Course level - The group mode defined at the course level is the default mode for all activities defined within that course. To use groups you need first to set a group mode in Administration > Course administration > Edit settings.
Activity level - Each activity that supports groups can also have its own group mode defined. If the course setting "Force group mode" is set to "Yes" then the option to define the group mode for individual activities is not available. If it is set to "No", then the teacher may change the group mode.
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