In discussing the OLPC project, a few people at Wikibooks had shown an interest in helping, but were undecided how to do so. Using Wikijunior we could write books for the children recipients of these laptops to use for independent learning. However, as many of these children are not native english speakers, it's difficult for us to do anything directly. We could write a book with the expectation that it be translated "on the ground" by volunteers into whichever local language was necessary.
The concept also arose that we could write a book about the english language, that is a book designed to teach a non-english speaker to speak basic english without reliance on the reader's native language. Basic ideas about this involved a heavy reliance on images to associate simple words with common objects. Possibly even audio files could be added for help in pronunciation. This seems like an awfully anglo-centric solution to an unrelated problem and so this idea was scraped (at least for the OLPC project, this idea has plenty of merit among illiterate children in english-speaking countries).
From that idea we found the concept of image-based learning. We could use pictures and symbols, almost to the exclusion of all words, to teach basic subjects in a language neutral way. Using the imagemap extension we were able to come up with a proof-of-concept for the idea in [[Wikijunior:Colors]]. For the colors book, the table of contents is completely image-based: Click on a color to go to the page about that color. There are some english words in this book because it was originally designed as a simple read-along for parents and infants.
The next idea on the table was a mathematics book, which is slowly coming to fruition in the form of [[Wikijunior:Visual Math]]. This book has highlighted the need to create a large number of images representing quantities and basic arithmetic operations (addition, subtraction, counting, etc). There are some images for this purpose available on commons, but not nearly enough to complete this book. To that effect I would like to post a call to all wikimedian artists to help generate images for use in this book. Images of items in various quantities are needed most importantly (so that numbers can be directly associated with object quantities), although images that represent changes in groups according to arithmetic operations are also needed. There really is a lot of room for creativity here. I sweep through commons regularly, so images that appear in [[commons:Category:Arithmetic]], will be found and employed readily. If we can collect a large enough group of images we might even need an additional category ([[commons:Category:Numbers]] appears to already be used for a different purpose).