Once you've created some Class Activities, there are a few different options to make them easily accessible for your students.
Students can always access and complete their activities by simply logging in to Spaces, and clicking on the Activities tab within your class.
As a teacher, you can also click on the Share button on any activity in your account:
From there, you'll see two options:
You can copy and paste the Activity URL to share a specific activity with students via email, messaging, within an LMS, or really anywhere you can link a URL
You can click Share to Google Classroom, and log in with your Google account, then follow the prompts to post the activity URL as an assignment or message within any class you've created in Google Classroom
Either way, your students can click on the link, log in with their Spaces account (if they aren't already logged in), and they'll be brought directly to that activity.
You can also use the Activity URL to share a specific activity link with other co-teachers in your class!