To help students develop an understanding of the proper use and function of spectrographs and monochromators we describe a student-assembled spectrograph using a "webcam" detector. The apparatus also works well as a low-cost demonstration, helping students make connections between an atomic spectrum observed by eye and a plot of the relative intensity versus wavelength. It also allows students to observe the internal components of a spectrograph. (Contains 3 footnotes and 3 figures.)