The history of writing to learn college science is tied to the development of laboratory methods. Such student-centered learning was widely hailed in the 1890s as student enrollments increased dramatically and a backlash grew against lecture and recitation methods. However, as the author shows using archival examples from Dartmouth College, Amherst College, and the Massachusetts Institute of Technology, science educators have too often relied on reductive measures of students' grasp of content rather than the kind of argument about scientific findings that is the stuff of real scientific writing and of real science. Although some contemporary science educators continue to tout the value of writing to learn science, the laboratory report or research article itself is a genre that dominates student activities but still largely suffers from the ills of its predecessors. Ultimately, the author calls for a renewed focus on laboratory writing, for both science education and writing studies, to fulfill the promise of previous reform efforts. (Contains 5 figures and 1 note.)