The Curtain WallJoel figured only five or six people, tops, would see the end result. Most of them would ignore it. But there was a chance that one person would appreciate it. That one person—whoever it might be—was worth his effort. “Joel!” He put his hands on the maple tree and leaned forward. He studied the ground for a second, then stretched his right leg as far as he could. “You can do this,” he said, mimicking the too cheery voice of his ninth-grade algebra teacher, Mrs. Kane. The first two footprints were perfect. The third could have been better. “Joel!” He repeated the procedure on the left side of the tree. “Now for the tricky part,” he said, imitating the gravelly, I’d-rather-be-anywhere-else-than-teaching-you-bastard-kids voice of his history teacher, Mr. Beckson. He hopp

