Why do objects sink or float?

A kindergarten teacher demonstrates her science subject knowledge in planning and implementing an investigation about 'floating and sinking'. The teacher has clear goals for her student learning and supports colleagues to select and apply effective teaching strategies to refine and extend students' understanding of the concepts in focus. In a lesson, she engages students in language development, critical thinking, using hypotheses and testing their ideas through experiment and discussion. The teacher reflects on what students have learned with a kindergarten aide, identifying future interventions to correct misunderstandings. Together they plan where students' thinking might be taken next.

Ulverstone Primary School in rural Tasmania was established in 1870. It is now a large primary school of 420 students. In the kindergarten class, students have been learning about 'floating and sinking' in a series of science lessons. The teacher and the teaching aides have organised activity areas designed to build students’ understanding. At water trays, children engage in independent and guided exploration about 'How a boat can be made to sink' and 'How a heavy object can be helped to float'. Relevant fiction and non-fiction texts and writing and art materials are provided for students to record their understandings. The teacher and assistants scaffold students' observation, hypothesising, prediction, experimentation and tentative interpretation of data, embedding appropriate scientific terminology in experiential learning.