While Google Slides can be viewed as limited in reference to animations, it seems to support one cool feature, animated gifs. Animated gifs are images that usually loop over a few frames, such as this volcano:
It’s a pretty spiffy way to spruce up a presentation! To find animated gifs, you can go to Google Image Search and search for your term.
That will return a list of images, but they won’t be animated! Click on the Search Tools.
And under Type, you can select animated.
Now the search results will be showing animated pictures that should work in Google Slides. Be sure to click on View Image to show the image, and then you can copy the url and use it to add images to your Google Slides presentation.
This also can be used with animated gifs created by students. Instead of just putting a static image in their presentation, they can create a short video that can be converted to an animated gif. There are also apps for mobile devices to make that easier.