Stop Motion Animator is a cool Chrome App that lets you create stop motion animation on a Chromebook. IPads have had this capability for some time, and many teachers successfully used Google Slides for this functionality on Chrome OS.
Some time back I used iPads with a group of 5th grade students to create claymation videos. Stop Motion Animator would be ideal for such an activity. The first techno-issue we run into is few Chromebooks have dual webcams, and its rather difficult to record with a webcam selfie style.
I bought an HD Creative Labs Web Cam last year for my Linux desktop. Since it does not get too much use there I was curious if I could hook it up on my HP 14 Chromebook for a dual use webcam capability. It worked perfectly, I just chose Camera 2 in the Stop Motion Animator app. The webcam I am using currently is less than $20 on Amazon.
I found Stop Motion Animator very easy to use. Every time the frame was changed the user would simple click capture. When the animation is finished you can choose slow or faster to get the best speed for captured frames. It saves the video in .webm format so it can be viewed natively on the Chromebook or the web.