The tiling patterns above were produced using Repper, a patterning/tessellation program that has a selection of wallpaper groups available (as well as some other effects). The program allows you to load an image and select part of it, to which it applies its symmetry transforms. As well as some very straightforward symmetry groups with visible edges (p1, pm, pg, cm and others), there are a set of ‘seamless’ groups that give much prettier results as can be seen above. The original image was of a forget-me-not flower and the various patterns were produced by moving the selection window and changing the symmetry. There’s a limited, trial version of the software available on the Web here. Repper isn’t primarily intended as a tool for teaching symmetry but it does give aesthetically very appealing results which can help in gaining students’ attention and interest at the beginning of a course or unit. Also, it’s great fun for anyone who has ever enjoyed playing with a kaleidoscope!