Tokyo Juku. Detective Hiroshi Series, #7

In Japan's high-pressure exam world, truth is the hardest test of allEighteen-year-old Mana pulls an all-nighter at her juku, a private Japanese cram school that specializes in helping students pass the once-a-year exams. She failed the year before but feels sure she'll get it the second time-if she can stay awake. The Japanese saying, "Four pass, five fail, " presses her to sleep just four hours a day, and study the rest.
When she wakes up in the middle of the night, head pillowed on her notes, she takes a break down the silent hallway. A light comes from an empty classroom, and still sleepy, she pushes open the door to discover something not covered in her textbooks. Her juku teacher, the one who got her going again, lies stabbed to death below the whiteboard, with the knife still in his chest and the AV table soaked in blood.
Detective Hiroshi Shimizu is called in, and though he's usually the forensic accountant, not the lead detective, he's put in charge of the case. With the help of colleagues old and new, he's determined to find the killer before the media convicts the girl in the press, the new head of homicide pins it on her, or big money interests make her the scapegoat. Hiroshi follows up on uncooperative witnesses, financial deceptions, and the sordid details of some teachers' private lives.
Even as he gets closer, the accumulating evidence feels meager amid the vastness of the education industry, and the pressures and profits of Japan's incessant exams. At the outset of the investigation, Hiroshi listens as an education ministry official lectures him on how education holds the nation together, but he soon discovers how it also pulls it apart, and how deadly a little learning can be.