Year level: Year 6

Strand: Number

Lesson length: 50–60 mins

In this lesson, students gain awareness about water usage associated with common activities around the home. They use a modelling approach to work towards determining an approximate answer to the question ‘How much water does our class use at home?’ They enhance their proficiency in reading and saying numerals beyond 1000 out loud.

This lesson is the first of 5 lessons that connect the cross-curriculum priority of Sustainability with Number, Measurement and Statistics. It can also complement the science content description AC9S6U04.

### Achievement standard

Students use estimation to find approximate solutions to problems involving rational numbers and percentages. They use mathematical modelling to solve financial and other practical problems involving percentages and rational numbers, formulating and solving the problem, and justifying choices.

### Content description

Use mathematical modelling to solve practical problems involving rational numbers and percentages, including in financial contexts; formulate the problems, choosing operations and using efficient mental and written calculation strategies, and using digital tools where appropriate; interpret and communicate solutions in terms of the situation, justifying the choices made.  AC9M6N09

### General capabilities

Numeracy

Sustainability

• Futures (SF2)

Exit ticket:

1. Write down an estimate of a person’s very high daily water use at home (uses a lot of water).
2. Write down an estimate of a person’s very low daily water use at home (uses very little water).

Expected answers: 1. values above 200 litres per day 2. values below 140 litres per day

• Read, write and interpret numbers up to 1000
• Read and interpret a column graph
• Understand that an average is a single number that represents a set of numbers
• Know the number of days in a week, month and year

Language

• assumption
• average
• estimation
• household
• litres
• per person

Some students may:

• require support read and speak numbers beyond 1000
• find it challenging identifying and interpreting important information from a water bill
• require support to make assumptions to approximate values.