searching google and freshmeat didn't seem to work.
It's bad that you were forced to fallbak to Linux by such situation, but I think there are greater chances to improve such software in Linux.
I think the development community will very gladly help people in need of their "services"
and from what i've seen so far, they can create some of the most original and inovative software you can think of.
I suppose such programs do not demand a great effort on the programmer and can easily be scriptable, so people like you can alter the behavior of the app fastly according to the children need's without need to learn a fully featured language.
open-source concept will also help, probably many "edutainment" apps when modified could be of some help and improvements can be made whenever necessary.
anyway, before such software is created, you might want to stick to using wine as DirtDart
And what are the legal issues involved with those win apps? maybe we still could get something out of them for further development or at least show them to the developers of the linux versions so they get the ideia.