Students use repositionable, self-stick notepaper to model superposition, crosscutting relationships, folding and faulting, intrusions and unconformities. This method makes stratigraphy concrete and understandable as it explains the principle of superposition as it connects to relative dating. Handouts: Stratigraphy Strategy: Modeling processes with Post-Its (R) (PDF - 20MB) Post-It Stratigraphy (.zip file - 27MB)