Efi Chalikopoulou for NPR Efi Chalikopoulou for NPR The SAT, a college admissions exam that for nearly a century was completed using paper and pencil, is now officially all-digital. This week, students in the U.S. will begin taking the new SAT on their own devices — including a tablet or a laptop — or on school devices. The test is also one hour shorter (down from three hours), has shorter reading passages and uses digital tools, like a highlighter, a graphing calculator and a bookmark to go b...