While there are many ways to schedule a hangout from classroom (using the class calendar or inviting the class list) the easiest way may be to notify students before and then schedule the meet to appear the day of the event
First Create the Google Hangout in your calendar. See directions HERE.
Once you have the event – copy the Google Meet link. Then go to classroom.google.com
At the top – go to the classwork tab and then Create an Assignment. Fill in all the information. Under the ADD button paste your Google Meet link. Click next to the Assign button and schedule a time for it to post.
Schedule the time about a half hour before your meeting and it will automatically post to your classroom.
