Some Perspective Papers:
 The future of secondary school geometry
 Justifying and proving in geometry
 The role and function of proof in mathematics
 Habits of mind: an organising principle for curriculum
 Alternative instructional strategies for geometry education
 Massachusetts curriculum framework

Some links:
 Connected Geometry
 Geometry and the Imagination
 The Geometry Junkyard
 The Geometry Centre
 Polyhedral Solids
 Polyhedra in the classroom
 World of Esher
 Mathematical art of MC Escher
   Mathematics and Art at Dartmouth College
 Tessellation tutorial (see especially Where's the Math in Symmetry)
 Geometry web discussion
 27 proofs for Pythagoras
 The Divine proportion WARNING: you may be fascinated/shocked/offended . . .
 Graphics gallery
 Euclid's Elements All the books, and dynamic!
 Dynamic Java Applets
 Geobord activities
 Tangram activities