In multilingual schools students have diverse identities, cultural backgrounds, perceptions, capacities and linguistic experiences. The space for teaching and learning is also mediated by stereotypes and prejudices associated with this diversity. Diversity, stereotypes and prejudices shape how teachers and learners operate in a world of complex social relationships. In this survey we explore the hidden attitudes of immigrant students and teachers in secondary education in Catalonia (Spain). The research uses the distinction between explicit and implicit attitudes to analyse immigrant students' perceptions and teachers' subconscious perceptions about school involvement. The sample includes 4078 immigrant students with more than six months of residence in the host country that were attending linguistic support classes in secondary schools of Catalonia during the year 2006-2007, and also their regular classroom teachers and support teachers. The survey aims to establish if is there any statistically significant associations between the attitudes of newcomer students and teachers, and the linguistic and geographical origins of the students. We wanted to know if teacher and student perceptions agreed or differed and to characterise stereotypes and prejudices affecting positive or negative attitudes about the organisation of teaching while learning. The results show how the teachers' perceptions about newcomer students' involvement differ in many cases from the views of the students, and how lower expectations and subjective manifestations of racism are evident with some groups, especially with students of African origin. (Contains 6 notes, 11 tables, and 1 figure.)