I have been playing around using Picasa and a few other image editors I found, trying to see how you could use these programs in the classroom. My point of view is that it is more about the creation of a slideshow or collage that makes these programs useful in the classroom. Students would be able to edit images better using lighting effects and cropping but it is the application of these images that assists learning. Students would be able to create slideshows similar to Photo Story and make collages with interesting backgrounds and borders to show their process of learning in the classroom. Creating a collage of a semester of work of a group task to show the class helps to consolidate and share learning.
I found this blog which also outlines a few other ways to use image editors in the classroom, I really like the idea of creating a puzzle though I haven’t found a good program for this yet.
I looked into the Avairy program though it is not something I would generally use in a primary classroom as it is quite advanced and has a similar layout to Photoshop. Though it has many different editing programs available and it is still free. Avairy also offers an Audio Editor which from what I have had a look at is fairly easy to use.