You can look up your group's join code by clicking on the "Invite Members" button next to the group’s name on the group page. You will be taken to a page where you are shown join code information for that group.
The invite page for your group will display the group's join code inside the "In Person" box. Write down the code, or click “Copy Code” so that you can copy the code to your clipboard so that you can paste it into an email message or document.
Step-by-Step
Navigate to your team's groups page by clicking on the team’s name in the main menu, and then clicking on "Groups."
Click on "Invite Members" next to the group that you need to add students to
On the group's invite page, the join code will be listed inside the box labeled "In person." Write down the code or copy it to your clipboard by clicking “Copy Code.”