I was especially excited by how the kids are interacting with the content in the videos. They were reading and writing the word, then listening to the word, and cheering quietly for themselves when the movie confirmed that they had read the word correctly. I heard repeated exclamations of, "I read that one right!" and "I knew that one!" It's always tricky to design materials that will have kids engage actively with the content, rather than just clicking along, and it seems that these videos have worked for this group of kids.
I'll also say this about making media for kids: use music. Danceable music. I deliberated about this a little bit, but I found that having a little beat running through these videos really kept things fun and engaging for the kids and seemed to help them focus. Plus, who doesn't like a good beat?