An enrichment unit in basic geometry and symmetry, including translation, tessellation and reflection, ideas on line designs and knot designs for teaching lines and line segments, and ideas for daisy designs to teach... <a href="http://www.yale.edu/ynhti/curriculum/guides/1993/1/93.01.10....">http://www.yale.edu/ynhti/curriculum/guides/1993/1/93.01.10....</a> more info