http://metamoracommunityprek.blogspot.com/2010/12/puzzles.html
This puzzle is HARD!
http://metamoracommunityprek.blogspot.com/2011/11/pattern-play-puzzle.html
More difficult puzzles that we place in the Discovery Center---
http://metamoracommunityprek.blogspot.com/2015/01/national-puzzle-day.html
