My reasons were just pure curiosity. Just to see how the kids would react, and how they would engage with creating their own central ideas. I was not at an official PYP school, so there was no exhibition. This year however, there is an exhibition, and its coming up fast. My reasons for hiding the central idea and having kids create their own is more pragmatic. It is scaffolding and preparation for when they have to do it themselves.
This year though, I am not framing it as a guessing game. Last year they were trying to figure our what it said under the paper. My hope was that they would compare their CI to the one the curriculum provided and find the pros and cons. They did that, but I was uncomfortable with the idea of them trying to guess. This year, we will be making our own CI and debating the differences with our classmates. I can't say where it will go, but my hope is that some shared language emerges from these debates, and the students begin to influence one another (and that they see how they are being influenced by others).
A few of my colleagues were at a workshop a couple of weekends ago with Lynn Erickson, and one of the more interesting ideas that emerged was that of leaving the Central Idea on the planner and not sharing it with the students (I love how even though I wasn't there, I can still join in the discourse).
This just makes sense. If we all view the world differently, and we all have our own interpretations, and those interpretations are valid; then why do we have one CENTRAL IDEA? That seems to be a bit too top down for me. I believe the real learning comes from the bottom up, and is emergent, and impossible to predict ahead of time.
There is a great discussion on PYPthreads if you would like to read more. I will quote the beginning, which was started by @FrostChrissy, to get you curious to read more and join the discussion:
This subject has been niggling at me for quite some time. I think it's fair to say that there is an assumption in most PYP schools that we should have the central idea on display in our classrooms. I for one have poked my nose into classrooms to police their presence in the past. I thought I was doing the dutiful PYP Coordinator thing. But isn't this counter-inquiry practice?! By displaying central ideas, aren't we telling the students the 'answer? Surely this is in opposition to constructivist/inquiry learning?!