A study investigated the effects of home language and some bilingual instructional practices on language minority or bilingual secondary students' learning of English as a second language. Subjects were 17 teachers and their students from 12 secondary schools in an urban school district with a high Hispanic enrollment. Teachers were observed for their interaction with students or others, settings in which the interactions occurred, purpose of the interaction, and specific behavior. Each was observed for 10 30-second intervals 2 separate times. Students' English skills were pre- and posttested using a standardized proficiency test and a locally-produced Spanish literacy test. Analysis of results indicates that, in general, cognitive processes in the bilingual classroom are teacher-centered, and peer group support in learning English was not emphasized. Teachers rarely placed students in pairs or small groups. It was also found that students' existing home language skills affected English achievement, as did some instructional strategies such as encouragement of self-management. It is concluded that first language skills should not be overlooked as an important foundation for second language learning, and that teachers should encourage students to manage their own learning. Contains 18 references. (MSE)