This research is an ethno-linguistic study of the development of the L2 oral proficiency of three case study participants at a Spanish immersion elementary school. The primary focus of the research was upon the correlation between language choices in a classroom, the quantity and type of L2 Output and oral proficiency development. However, the broader study also included an ethnography focused upon issues of investment, identity and language choices.

The three case study participants were observed in their second and third grade classrooms and were videotaped in home interviews over a period of four years. All data gathered was analyzed according to the following framework: (1) language choices; (2) communication strategies; (3) grammatical competence; and (4) sociolinguistic and discourse competence. Analysis of the data shows that there was a much greater quantity of L2 Output in the second grade classroom with a "Spanish Only" rule and group motivational system than there was in the third grade classroom with no "Spanish Only" rule.

All three case study participants conformed for the most part to the "Spanish Only" rule in second grade, but their adherence to the rule appeared to be motivated by different factors. Despite their very different identities and roles within the classroom, some aspect of the motivational system prompted each of them to speak the target language for the majority of their interactions with peers and for all of their interactions with their teacher.

In third grade, the lack of any rule or motivational system appeared to trigger a significant reduction in the amount of L2 produced by the case study participants, although the reduction varied considerably among the participants. The decrease in the quantity of L2 Output in the third grade classroom appeared to correlate strongly to a decrease in competence. Noteworthy among the changes evident in the oral proficiency of all three participants were the increase in reliance upon communication strategies and the decrease in the ability to employ L2 syntax and verbal morphology.