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4) At the top of the Team look for the 'students are waiting to join' message and click 'Activate'
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5) You’ll receive a prompt asking if you’re sure that you’d like to make the class team visible to students, click 'Activate' to continue.
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If you’re not able to see the Activate button, please quit your Teams client and try again. If the Activate button is still missing, please visit https://teams.microsoft.com login, and activate the class team from there.