One of the things I love being able to do with Google Slides is have all students in the class collaborate on a single Slides presentation. This gives me one document to open and assess. I can give feedback to students while they are working on the presentation. Students can see the contribution of other students easily. Peer evaluation is a snap. It is also super simple to project the work of everyone in the class to share student work and to facilitate discussion.
In Google Drive create a Google Slides presentation for the students to contribute to. I recommend having a title slide first and the directions for the students to follow on the second slide.
Assignment in Classroom
After students add their slide to the collaborative presentation, they will want to copy the URL from their slide. Each slide has a unique slide ID in the URL. If a student is on slide 32 and copies the URL on that slide, the link will go directly to slide 32.
When assessing student work, you go to the assessment view of the assignment. Click on each student and click on the link they turned in. Each link will go to THAT students slide. This makes it a lot easier to assess collaborative student work. You know exactly what contributions each student made and can provide feedback easily, and privately, right in Classroom.