
I like blackboards, and I like REAL ones and BIG ones that you won't find at Pottery Barn. In looking for a source, I spotted this one in the window of the JCrew shop on Prince. These guys are in New Jersey actually, but they stock a large supply of blackboards and related products that mainly go to schools. You can get these up to 4' x 12'...

Store stylists are smart people, and JCrew has some really good ones, so if this is their source, you know it's a good one.
NYBlackboard stocks both Porcelain-on Steel (for heavy use in schools) and Lastoplate boards (lastoplate is a water based paint over a hardwood backing and only for light use). They also stock both hardwood and aluminum frames (in colors!).
>> New York Blackboard

And since you can do chalkboards this big, it's easier to imagine making a big headboard out of one:

>> Look! A Chalkboard Turned into a Headboard
We love our "big board" and had it made for about $75.00.
The frame is trim from Home Depot painted with Ralph Lauren gold paint.
http://farm1.static.flickr.com/165/426622629_b978875b7a.jpg
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