Go! Animate is a site that allows you to create animated videos, for free. There is also a school account that is private and secure, has school safe content, content moderation and group management, starting at $8 per month.
The free account lets you create videos easily and quickly. You can also add your own recorded voice to the videos and it is easy to share the videos to YouTube, Facebook, and more.
The free account is limited to 2 minutes per animation. You can create your own characters or use the pre-made ones, including some from Star Trek and It's Happy Bunny.
This could be a fun way for students to create a project that demonstrates their understanding of a concept or for digital storytelling.