A class with a strong sense of community tends to be a productive space for learning. Focus attention on developing a community among your students and also connecting with them personally.
Many instructors design their classes to be active learning communities, and so develop a culture of sharing among students. In terms of class activities, you can facilitiate this culture by carefully designing peer review and in-class workshopping to help students learn to support one another in their writing and speaking; similarly, organizing activities around collaboration and group work can also foster a culture of generosity and sharing.
Some instructors have students keep open writing and speaking portfolios through the online platform to facilitate the ready sharing of student work among classmates. Although Canvas itself does not provide a ready means to create such open portfolios, several instructors use Stanford Box in addition to (or instead of ) Canvas to set up Student Folders that are accessible by the entire class, where all student materials -- from drafts, to in-class writing, notes, revisions, and even peer review responses -- can be uploaded and shared.
If you're considering an open learning community of this nature, you should include community guidelines on your syllabus and also discuss them (and perhaps even develop those community guidelines collaboratively) with your class. You might also want them to sign a permission form to formalize their acknowledgement of how their work will be shared.