We tend to think that students have gotten less disciplined over time when it comes to their schoolwork. But some findings from Erik Kwakkel, a historian at The Netherlands' Leiden University, show that students have been zoning out during lessons for at least 800 years. Over at his blog, Kwakkel posts images of fascinating finds from historical textbooks. Among them — students' doodles from the 13th- through 15th-centuries!