Impact of changes to the income tax system
Access denied
Introduction
In this activity, students explore whether the stage 3 tax cuts are equitable, the extent to which they will address bracket creep, and their impact on government revenue. It provides an opportunity for students to use mathematical modelling to solve practical and real-world problems involving rates in financial contexts.
Achievement standard
By the end of Year 8, students recognise irrational numbers and terminating or recurring decimals. They apply the exponent laws to calculations with numbers involving positive integer exponents. Students solve problems involving the 4 operations with integers and positive rational numbers. They use mathematical modelling to solve practical problems involving ratios, percentages and rates in measurement and financial contexts. Students apply algebraic properties to rearrange, expand and factorise linear expressions. They graph linear relations and solve linear equations with rational solutions and one-variable inequalities, graphically and algebraically. Students use mathematical modelling to solve problems using linear relations, interpreting and reviewing the model in context. They make and test conjectures involving linear relations using digital tools.
Students use appropriate metric units when solving measurement problems involving the perimeter and area of composite shapes, and volume of right prisms. They use Pythagoras’ theorem to solve measurement problems involving unknown lengths of right-angle triangles. Students use formulas to solve problems involving the area and circumference of circles. They solve problems of duration involving 12- and 24-hour cycles across multiple time zones. Students use 3 dimensions to locate and describe position. They identify conditions for congruency and similarity in shapes and create and test algorithms designed to test for congruency and similarity. Students apply the properties of quadrilaterals to solve problems.
They conduct statistical investigations and explain the implications of obtaining data through sampling. Students analyse and describe the distribution of data. They compare the variation in distributions of random samples of the same and different size from a given population with respect to shape, measures of central tendency and range. Students represent the possible combinations of 2 events with tables and diagrams and determine related probabilities to solve practical problems. They conduct experiments and simulations using digital tools to determine related probabilities of compound events.
Content descriptions
Use mathematical modelling to solve practical problems involving rational numbers and percentages, including financial contexts; formulate problems, choosing efficient calculation strategies and using digital tools where appropriate; interpret and communicate solutions in terms of the situation, reviewing the appropriateness of the model (AC9M8N05).
Use mathematical modelling to solve practical problems involving ratios and rates, including financial contexts; formulate problems; interpret and communicate solutions in terms of the situation, reviewing the appropriateness of the model (AC9M8M07).
Teacher resources
In order to see the resources you must Register or Login if you already have an account.
Reading & Constructing an Income Tax Graph
Student learning resources
In order to see the resources you must Register or Login if you already have an account.
Reforming Australia’s income tax system
Changes to the income tax system
Other resources you might like
Suggested activity sequence
This sequence is intended as a framework to be modified and adapted by teachers to suit the needs of a class group.
Part A: Introducing Australia’s income tax system and stage 3 tax cuts
- Revise the concept of income tax and how it works. If necessary, play: How does Australia’s income tax system works.
- As a class, read about stage 3 tax cuts in the explainer. Invite student views on whether tax cuts are responsible and what trade-offs might be associated with them – such as government debt, less spending on services etc.
Part B: Constructing and reading graphs
- Explicitly teach students how to construct and read a piecewise graph. Eddie Woo has a video explaining how to construct a piecewise graph using tax brackets. Refer to: Reading & Constructing an Income Tax Graph – Video.
- You may also want to review how to use spreadsheets. Refer to Using spreadsheets – Visualiser.
- If necessary, review how to calculate the average rate of tax.
- Students complete part 1 and part 2 of the investigation.
Part C: Modelling and making decisions
- As a class, read about bracket creep in the explainer. Elicit student understanding of the concept and provide further explanations and examples if needed.
- Students complete the remaining parts of the investigation. Students may benefit from working individually and/or in small discussion groups.
- As a class, discuss students’ findings.