Hi Tim - we don't currently have support for that sort of graphics operation, but your students could certainly
implement it in the form of a nice geometry exercise! (Note: this would be a
very advanced project)
You'd be looking at a contract like this...
; wrap-text: String Number String Number -> Image
; consumes a string, size, color and circle-radius, and produces
; an image of that string, wrapped around an invisible circle of that radius
Your students would need to compute the width and height of each letter (using image-width and image-height), then rotate the letter and position it appropriately. By combining each rotated, positioned letter into a single image, you'd get the desired effect.