My autistic DS learns really well through DVDs - and pretty much learnt his alphabet, his numbers, colours and many other words through a combination of Baby Bumblebee and Jolly phonics DVDs. But I have never come across one that teaches addition or subtraction, in nice, visual ways. Anyone seen anything? I have tried Numicon on Moondog's excellent recommendation, but I'm looking for a DVD to play for him in wind-down time in the evenings.