The present study examined the use and effectiveness of a large corpus--the Corpus del Español (Davies, 2002)--in a 300-level Spanish grammar university course. Students conducted hands-on corpus searches with the goal of finding concordances containing particular types of collocations (combinations of words that tend to co-occur) and tokens (any occurrence of a word or sequence of words), then used these examples from authentic texts in order to better understand and use the grammatical concepts under consideration (e.g., preterite vs. imperfect, ser and estar). The study was designed to better inform language educators' understanding of the extent to which access to, and active use of, a large corpus helped students better understand and use particular grammatical concepts and structures. Qualitative and quantitative data obtained from a student survey offer evidence that the corpus was an effective learning tool and represented an innovative use of technology.