A wannabe student of drawing walks into Sarnoff and doesn't know her compressed charcoal from her vine charcoal. All these drawing tools appear dizzying. What contributes to the success of Sarnoff is that the store is staffed by artists--unlike that impersonal big-box crafts store, where customer service is an oxymoron. Remember how cool it was as a kid to get a new pencil box on the first day of school? Well, here, the organized displays of pastels and prisma colors, of watercolor crayons and oil sticks, remind us that the freedom of artful expression is still cool and within reach.