| It is widely assumed (Long 1983, Chaudron 1988) that native speakers (NS) modify their language in talk to non-native speakers (NNS), and that these modifications are beneficial for NNS language learning. In contrast, Verplaetse (1993) found that some native speaker modifications can have detrimental effects on NNS participation in NS-NNS conversation, thus lessening opportunities for language production, a crucial part of second language learning. Participation in talk is particularly crucial in school settings, where students are expected to develop communicative competence in academic discourse. This study thus explores the effects of native speaker (NS) teacher input on opportunities for limited English proficient (LEP) students to participate in science classroom discussions.; Three experienced science teachers (grades 7-12) were observed, interviewed, and videotaped 4-6 times over one year. Each classroom contained 3-4 LEP students who had been 'mainstreamed' from bilingual programs. Selected LEP students were also interviewed. Classroom talk about science was transcribed; teacher utterances were coded using a modification of Sinclair & Coulthard's (1975) classroom discourse code, then analyzed to assess differential distribution of speech act types.; Findings indicate differential use of utterance types. Teachers gave LEP students more directives to action (p {dollar}<{dollar}.05) than English proficient students received. In full class discussions, LEP students received fewer elicitations (p {dollar}<{dollar}.01). Questions to LEP students were lower cognitive level (p {dollar}<{dollar}.001 for two teachers) and more frequently closed rather than open-ended (p {dollar}<{dollar}.01 for two teachers). However, teachers called on LEP students who had not volunteered more often than non-volunteering English proficient students and, in lab settings, directed more answer-unknown questions to LEP students (p {dollar}<{dollar}.05 for two teachers). Overall, differences resulted in reduced opportunities for LEP students to participate in science discussions.; Teachers' unconscious modifications in talk to LEP students thus may frequently limit those students' opportunities for extended participation in discussions supporting decontextualized, higher-order reasoning. Proposed explanations for teachers' modifications include: (1) teachers' misperception of students' real language abilities, due to students' classroom performance and given the context specificity of language competence, (2) curricular and interpersonal time constraints, and (3) intention to shelter students from embarrassment. Compensatory teaching strategies are recommended. |
