Caroline Weaver, the own­er of CW Pen­cil Enter­prise, a spe­cialty pen­cil shop in Manhattan’s Lower East Side, has man­aged to make the dream of obsess­ives come true: What if this thing I love, this strange small thing, could be my job? For Weaver, that strange small thing is the humble pen­cil, and it has provided not only a business—celebrating its two-year anniversary this March—but a book as well, a his­tory of the pen­cil entitled The Pen­cil Per­fect. We chat­ted with Weaver about her store, the birth of the pen­cil craze, why Japan­ese pen­cils are so good, and why people think pen­cils con­tain lead. Here are twelve of the most fas­cin­at­ing things we learned.