Canes, I mean Keynes for Kids
And when you think you've seen everything... There is a website on Keynes for Kids (h/t Alberto Vázquez for the link)! Not sure how many kids would get the 45o degree Keynesian Cross (renamed after Samuelson in the site), but it's worth a try. If there are tons of sites about evolution for kids, why not one about Keynesianism.