While astrophysics is a fascinating subject, it hardly lends itself to laboratory experiences accessible to undergraduate students. In this paper, we describe a feasible astrophysical laboratory experience in which the students are guided to take several stellar spectra, using a telescope, a spectrograph and a CCD camera, and perform a full data analysis using the equivalent widths method on some spectral lines. This allows them to derive stellar temperatures after a suitable calibration and fitting procedure. On average, the estimated star's temperatures agree with the known results within an error margin of 5-10% for cold stars, and 20-25% for hot stars. (Contains 3 tables, 5 figures and 4 footnotes.)