I cut out puzzle pieces from white poster board (lucky that you have them pre-made AND free)
. I have the kids decorate them however they want ( I do this on the first day or so of school). Then we put them all together and hang in the hallway with a sign that says:
All the pieces fit in Mrs. BXXX's room!
We do this after talking about class rules and how we will be like a family and we have to work together and help each other. We are "connected." Hope this helps!