In conversation with Peter Merrotsy (11 Feb 2013) I noted that it was easy with large classes at Unis to get CAA up and running usefully, but I was failing to get schools to cooperate to get the user base up to economic sizes,
With Peter saying that this was all understandable I thought again. Why not use, from universities, the software and deliver it out to schools associated with outreach projects that they are already doing.
My guess is that WAJO might be a candidate,. Make it computer marked "Practice Past Papers" (but caution the users that in the real WAJO, their written solutions, and working, will be marked, and so clear exposition, not really taught in the CAA system, really matters too. Mind you, clear exposition towards a correct answer is the goal ...
The obvious person to work with on this one is Greg Gamble.
http://www.maths.uwa.edu.au/community/olympiad
http://enrichmaths.sponsored.uwa.edu.au/home/wajo/qnsandsolns
Well it worked once. Try
http://enrichmaths.sponsored.uwa.edu.au/?p=6631
http://maths.curtin.edu.au/courses/ttowns.cfm