From the great Edgalaxy blog:
Have you checked out our ever growing collection of amazing classroom posters and charts. We have been adding a new one every day for the last month and decided today was a great day to publicize it. We have an ever growing collection of maths posters, literacy posters and even student motivation posters that will turn any boring classroom into place of joy. All our posters are produced using high resolution text and can be up scaled or down scaled to suit your needs.
See on www.edgalaxy.com