Ever since I first arrived at Ravenwood I have been fascinated with the chalkboards in the classrooms. I was excited to find that they are craftable but I became so busy saving the Spiral that I forgot all about crafting one until I stumbled upon the recipe in my book earlier. There are other craftable signs as well, some are themed, Grizzleheim, Marlybone and Wizard City while others could be added to any house, Framed, Gravestone and of course, Chalkboard.
All but the Grizzleheim and Gravestone are 15,750 gold while they are 20,850 gold. I'm pretty sure that Koyate Ghostmane is over charging but don't tell him I said so. You can find him in the Baobob Market in Zafaria. If you don't want to actually craft them you can buy all but the chalkboard from the Crowns Shop. The price ranges from 299 for a chance of the Gravestone or Grizzleheim signs from different card packs to 1,500 crowns for the Marleybone themed one.
I was happily surprised that the signs can be set to say over 160 different things including 12 welcomes, 14 personalized tags, 42 school themed sayings, 13 beware notices, 31 warnings, estate announcements and 5 pages of miscellaneous messages. The selection allows you to be as friendly, unsociable or goofy as any wizard could want. And they just updated to add MORE!