There are few things left on earth that people have not attempted to measure. From temperature to time, from finances to football, numbers are a crucial mediator of how we perceive and understand the world we live in. Increasingly, however, it is humans themselves who are the subject of quantification. Our fitness and success, even our personality traits and attractiveness, are now the stuff of scales and scores. But what does it do to us to be on the receiving end of such measurement? One of the world's most successful global metrics is the school grade. Long predating the digital age, educational marks can be traced back at least to sixteenth-century European schools and have since conquered the world, becoming the indicator of academic achievement. To understand what it means to be quantified, Noëlle Rohde undertook in-depth fieldwork in a German comprehensive school where students receive more than one hundred grades per year. By staying close to the pupils as they are continually examined and assessed, her ethnography illustrates how marks mould students' self-images, how they enforce meritocratic thinking and serve as a potent disciplinary tool. Marked: School Grades and the Quantified Life not only offers a nuanced account of the effects of grades on students, but also tells a cautionary tale of the increasing quantification of human life.