I created a blank slide document for my students to do their individual slides. Then I want them to be able to copy what they've done and put it into one presentation. I know you showed me but I cannot remember how we were going to have them put everything into one document.
Ah . . . one of my favorite discoveries, the Web Clipboard! It is located in the Edit menu in almost all of the Google Apps. The coolest part about this is that there is no time limit between when you copy and when you paste, plus you can copy something on one computer and then paste it on another!
In this particular example, the students want to copy an entire slide they have made into a single slide on a presentation the teacher has made. To do this, start with the student slide. Just be sure that nothing on the slide is selected (just the slide itself); go up to the Edit menu, choose Web Clipboard, and click "Copy entire slide to web clipboard." Now each student can go into the destination presentation, click on their assigned slide, repeat the process, but click "paste slide" from the list. It looks like this:
One thing to note: if the student is pasting more than one slide into the destination presentation, he will have to copy each slide individually. That's ok, though, because anyone can have multiple things in his/her Web Clipboard!
If the student in this situation had wanted just a particular element from the slide, like maybe just the image and the caption, he could select those (hold the Shift key while you click to select multiple items), and copy them to the Web Clipboard. Items copied there will stay there until you click "Clear all items."
This is AWESOME when you create something today, but don't need to paste it until tomorrow or next week or next month. It's also perfect when you're working collaboratively with someone and you need something you've pasted in your Web clipboard to go into their document. Yes. You heard me. Their document. Once you've copied something to the Web clipboard, your elements can be pasted into Drawings, Slides, or Docs (but not into the newest version of Sheets). It's just sitting right there in your Edit menu, waiting to be used!