Adobe Voice (iPad only) makes creating video slideshows that have a voice over extremely easy. After a short tutorial, I jumped straight into making my first video (not a very creative effort I'm afraid). Making the recordings was as simple as holding down a button. If you make a mistake, you simply record over in the same way. Each slide lasts for as long as your recording so there is no messy fiddling around with timelines and making cuts. Moving your slide moves the attached voice over so it is easy to keep track of things. You can add photos (your own or from the web*), icons or text. To keep things simple, there are only five layout options for a slide and you have no way to change fonts and transitions. That is all handled by the theme that you choose. That lack of choice helps you to concentrate on the content rather than the design. Music options are also limited but the app provides enough variety for most projects. This simplicity would be a real strength when using in a classroom situation. It even compiles the credits for images used in the presentation (a nice touch of digital citizenship).
What is not so classroom friendly is the requirement to share only via the Adobe Cloud. Although access seems to be free, Adobe online offerings seem neither secure enough nor reliable enough for a school to depend on. At the moment, there is no option to save a video to your device for local viewing elsewhere (although you can play it on your device using the app). There is also no option to upload to popular sharing sites such as YouTube. Having to sign into an Adobe account would be a deal breaker for many schools.
Also a potential problem is the way it sources creative commons images for the slides. It seems to rely on some kind of Google search which may return (depending on search terms) material inappropriate for the classroom. It has also been suggested that not all images it finds actually have a Creative Commons license. The app itself says that you should check the license before using an image.
If you can get past those issues, I think this would be a terrific app to use with children. They could record a book review or a piece of persuasive language. They could use it to explain their thinking on a unit of work. They could even use it to record their pepeha. Teachers could use it to make short explains videos on whatever topic they need. If you are lucky enough to have an ipad, give it a go!