Amongst Australian EAL specialists there is increasing recognition of the value of incorporating students' home languages and cultural knowledge into teaching and learning. However there remains a need for guiding principles for developing effective multilingual and translanguaging approaches for linguistically diverse students. This paper presents some classroom approaches and suggest principles for effective multilingual curriculum and pedagogy. An ethnographic study in an Australian high school revealed that students used their multilingual repertoires to support learning individually, collaboratively and through access to external information. Teachers responded by rejecting, accepting or actively engaging students' multilingual resources. Analysis of teaching approaches suggests some principles for effective multilingual classroom practice. Successful multilingual pedagogies require both teachers and students to challenge the "monolingual mindset" (Clyne, 2008, p. 347) of Australian education. Attention to both vertical and horizontal dimensions of multilingualism (Heugh, 2018) is also crucial. Additional principles include affirming multilingualism, attending to affect, developing shared learning outcomes, defining a social purpose and addressing practical considerations. A key to success is that these pedagogies are developed from students' existing multilingual practices. It is hoped that proposing these principles can extend discussion and research around the use of multilingual resources in school-based learning.