Current higher education professional teaching positions in a formal classroom setting almost invariably require use of a system of grading. Most instructors assign variations on "A's," "B's," "C's," "D's," and "F's." While we often commiserate about the process of assigning grades, which may be as stressful for instructors as for students, the lack of conversation among instructors about the mysterious omission of the "E" is but one indicator of the many tacit assumptions we all make about the processes of grading in higher education. Given that the time and stress associated with grading has the potential to distract instructors from other, more meaningful aspects of teaching and learning, it is perhaps time to begin scrutinizing our tacit assumptions surrounding grading. Below, we explore a brief history of grading in higher education in the United States. This is followed by considerations of the potential purposes of grading and insights from research literature that has explored the influence of grading on teaching and learning. In particular, does grading provide feedback for students that can promote learning? How might grades motivate struggling students? What are the origins of norm-referenced grading--also known as curving? And, finally, to what extent does grading provide reliable information about student learning and mastery of concepts? We end by offering four potential adjustments to our general approach to grading in undergraduate science courses for instructors to consider. The letter grades most of us take for granted did not gain widespread popularity until the 1940s. Even as late as 1971, only 67% of K-12 schools in the United States used letter grades. While not an exhaustive history, this article aims to describe the main developments leading to the current grading system in the United States.