They've talked about what programming languages they're planning on using over here
but in theory you should be able to use any language that has a ARM11 package. For instance, we know that the Android OS uses JAVA so in theory it shouldn't be difficult to find a JAVA package. I believe the goal of the project is open source learning, so I doubt they'll have any officially associated programming language associated with the device or course material for that matter. It's up to us to decide how best to use the product for our needs.
As for my two cents go on the issue, I've done programming in C, C++, C#, Java, and even some Assembly. Java came the easiest to me, but if I were teaching a class aimed at teaching some basic programming skills, I would probably show them how to do the basics in all 4 of those languages and let them choose which language they wanted to do the assignment in. After all, the fundamental issues in programming are the same no mater what language you use. The only real issue is the syntax, and that's not hard to pick up for an entry level course.
As for the second issue, Private Charities in the UK do not have shares nor shareholders unless registered has a Community Interest Company. Which is to say, it is extremely unlikely that one could purchase shares in R-pi. But I guess we'll have to wait for an official response from them before know that 100%