Mathematics / Year 9 / Measurement and Geometry / Geometric reasoning

• TLF-IDM025324

In this sequence of three lessons, students use geometric reasoning to establish relationships between angles in polygons and go on to make generalisations using algebraic expressions. Students explore and enumerate right angles in a series of rectilinear polygons and generalise their findings. They then explore the number ...

• TLF-IDM021843

This lesson challenges students to apply Pythagoras' Theorem to explore a practical real-world problem. Students explore technology reliant on mathematical concepts. The lesson is outlined in detail including curriculum links, vocabulary, materials needed, sample answers, discussion points and student resources such as ...

• TLF-IDM025322

This sequence of two lessons explores how statistical techniques that rely on randomly generated data can be used to solve problems. In the first lesson, students compare different methods for calculating the area of an irregular shape, using the context of oil spill maps. They are introduced to the Monte Carlo method for ...

• TLF-IDM025321

This sequence of two lessons investigates gradient and angle by applying the tangent ratio to find the angles represented by a road sign or the angle of a street. In the first lesson, students research what a road grade is and determine the actual angle of a road given its grade. They then construct their own road sign ...

• TLF-IDA004064

This work sample demonstrates evidence of student learning in relation to aspects of the achievement standards for Year 9 Mathematics. The primary purpose for the work sample is to demonstrate the standard, so the focus is on what is evident in the sample not how it was created. The sample is an authentic representation ...

• TLF-IDM020733

This resource is a web page containing an investigative task to explore volume. Derive the formulae for the volumes of a square-based pyramid and a cone, using mathematical concepts. A printable resource is also available to support the task. This resource is an activity from the NRICH website.

• TLF-IDA003207

This planning resource for Year 9 is for the topic of Volume and surface area: cylinders. Students calculate the surface area, volume and capacity of cylinders and solve related problems.

• TLF-IDM021659

When completed, the Square Kilometre Array (SKA) project will be the largest and most capable radio telescope available to scientists. Radio telescopes like the SKA detect radio waves produced by events and objects in the furthest reaches of space, translating these waves into data and imagery that allow scientists to study ...

• TLF-IDM016660

An animated introduction to the basic trigonometric ratios.

• TLF-IDA003210

This planning resource for Year 9 is for the topic of Time and duration. Students are introduced to expressing numbers in scientific form. This descriptor applies scientific form specifically to time. Students require a good understanding of place value and powers of ten. Students should know where the notation is used ...

• TLF-IDA002780

This lesson is designed for students to learn about car ownership in Australia and the real costs of buying and running a car. Students explore car ownership statistics in Australia, investigate the range of decisions people make about transport, calculate and compare costs of transport and make decisions on additional ...

• TLF-IDM016790

A 2D Shapes tool that can be used to create geometric objects such as quadrilaterals, circles, triangles, lines, arcs, rays, segments and vectors on a coordinate grid. Plot and label the vertices to reveal the internal angles, side lengths, area and perimeter, then manipulate the shapes on a grid to transform their shape ...

• TLF-IDM008603

This is a 22-page guide for teachers. The module introduces the idea of direct proportion and illustrates its many uses in science, commerce and measurement. It looks at ratios, gradients and fractions. A history of the development and use of proportion concludes the module.

• TLF-IDM009036

This is a 17-page guide for teachers. It continues the discussion of factorisation. In particular, the techniques for the factorisation of quadratic expressions are presented.

• TLF-IDM008605

This is a 23-page guide for teachers, providing an introduction to the financial mathematics component of the number and algebra strands for years 9 and 10. A brief history of the concept of money concludes the module.

• TLF-IDM008608

This is a 20-page guide for teachers containing an introduction to the three basic trigonometric ratios. A history of trigonometry concludes the module.

• TLF-IDM008823

This is a 17-page guide for teachers. It contains the definitions, properties and tests for parallelograms and rectangles. Proofs of the properties and tests are given. Constructions for parallelograms and rectangles are given.

• TLF-IDM008601

This is a 15-page guide for teachers containing explanations of the derivation of formulas for the areas of parallelograms, trapeziums, rhombuses and kites. Formulas for the volumes and surface areas of prisms and cylinders are obtained. Applications of these formulas are given. A history of the development of these concepts ...

• TLF-IDM012146

This is a five-page HTML resource about solving problems concerning surface areas of prisms. It contains one video and five questions, two of which are interactive. The resource discusses and explains solving problems involving determining surface areas of prisms to reinforce students' understanding.

• TLF-IDM015626

In northern Queensland's Gulf region, some farmers use GPS mapping to help manage their extensive properties. Use this clip as a context for applying your understanding of area, in particular your understanding of conversion between square kilometres and hectares. Apply trigonometry and Pythagoras' theorem.

• TLF-IDM013745

This is a website designed for both teachers and students that addresses simple interest from the Australian Curriculum for year 9 students. It contains material on calculating simple interest. There are pages for both teachers and students. The student pages contain interactive questions for students to check their progress ...

• TLF-IDS4972

These seven learning activities, which focus on the use of 'real data' using a variety of tools (software) and devices (hardware), illustrate the ways in which content, pedagogy and technology can be successfully and effectively integrated in order to promote learning. In the activities, teachers use the three content strands ...

• TLF-IDM013744

This is a website designed for both teachers and students that addresses scientific notation from the Australian Curriculum for year 9 students. It contains material on scientific notation using index laws and multiplication, division and indices. There are pages for both teachers and students. The student pages contain ...

• TLF-IDA003204

This planning resource for Year 9 is for the topic of Pythagoras and trigonometry. Students develop and use their understanding of the relationship between the corresponding sides of similar right-angled triangles.

• TLF-IDA003654

This lesson explores how poker machines work and what is meant by the term Return to Player (RTP) percentage. Students run simulations to determine how small betting amounts can lead to a large cumulative loss over time and examine how reinvesting profits or wins from playing the poker machine back into the machine has ...

• TLF-IDM016554

Interactive activities that guide students to consider the use and presentation of geometric reasoning.

• TLF-IDM016264

Interactive activities that guide students to investigate properties of parallelograms.

• TLF-IDA003566

This comprehensive resource describes the progression of number-related ideas showing the relationship to other curriculum strands. The resource demonstrates examples of relevant teaching strategies, investigations, activity plans and connected concepts in number including teaching and cultural implications.

• TLF-IDM017688

What do you know about Pythagoras? Join Vi Hart as she not only explains his theorem but raises some legends about his dark past! Follow Vi's timeline of famous mathematicians to find out in which century Pythagoras lived. See how Vi shows a proof of his theorem and raises what was a big dilemma for Pythagoras: the irrational ...

• TLF-IDM025250

Think credit cards are basically free money? Gen Fricker will make you think again. Learn how interest rates and fees affect the money you borrow, and why they may be more expensive in the long run. Oh dear! Then test yourself with ASIC MoneySmart's "Things to think about" classroom exercises.  

• TLF-IDM025252

Compound interest will be one of the most important things you ever learn. Don't believe it? Gen Fricker will explain why. Learn how compound interest works, and why saving now can help you later. Game changer! Then test yourself with ASIC MoneySmart's "Things to think about" classroom exercises.

• TLF-IDM024895

There is a saying: 'climate is what you expect and weather is what you get'. |Understanding climate change is very difficult for most people, especially when the weather we experience is different from the information we are given by scientists about the climate changing. The difference is that weather reflects short-term ...

• TLF-IDM021608

Bees are necessary for assisting many plants to produce the food we eat, including meat and milk. Colony collapse disorder, which describes the disappearance of beehives, could have catastrophic effects on food production. Australian scientists are applying their maths and science knowledge to build up a picture of a healthy ...

• TLF-IDA003205

This planning resource for Year 9 is for the topic of Mathematical modelling. Students continue to solve mathematical problems from the real world around them. They draw upon knowledge learnt in the area of Measurement.

• TLF-IDM024991

How can you place four trees exactly the same distance apart from one other? By making a model! By using miniature trees to make a model of the problem, it becomes clear that a 2D solution is impossible. We learn how objects can help us visualise the problem situation, which in this case requires a 3D solution: a tetrahedron.

• TLF-IDM024946

Are triangles really the strongest shapes ever? If so, why? Learn how and why right-angled and equilateral triangles have been used in engineering, architecture and design through the ages.

• TLF-IDM016697

In this laptop-friendly resource, students consider the difference between volume and surface area before posing practical problems. They then consider issues relating to unit conversions and similar figures.

• TLF-IDM016249

Students construct a series of GeoGebra applets that investigate the parameters gradient and intercepts of straight lines. They reinforce this knowledge with Microsoft Math 3.0. 

• TLF-IDM016150

A page with a focus on using GeoGebra to enhance student understanding of various geometric properties and the importance of reasoning in proof. A laptop-friendly resource that includes supporting activities and links to resources.

• TLF-IDM020743

This resource is a web page containing a problem solving task that requires an understanding of Pythagoras' theorem. The task involves finding the area of shaded region with a circle with a known area. To solve the problem students need to establish a right angled triangle and apply Pythagoras' theorem. A printable resource ...

• TLF-IDM025251

Gen Fricker makes income tax interesting! Learn about income tax - what it is, how it works and when you have to pay it. Easy-peasy! Then test yourself with ASIC Moneysmart's "Things to think about" classroom exercises.

• TLF-IDA003560

This comprehensive resource describes the progression of geometric reasoning. The resource demonstrates examples of relevant teaching strategies, investigations, activity plans and connected concepts in geometry including teaching and cultural implications.

• TLF-IDA002781

This lesson challenges students to explore the pros and cons of various payment options, how they spend their money, different consumer products and where to go for more information about saving money and debt. During the lesson, students investigate multiple payment options to choose those that suit their circumstances, ...

• TLF-IDM013746

This is a website designed for both teachers and students that addresses coordinate geometry from the Australian Curriculum for year 9 students. It contains material that shows the connection between algebra and geometry through graphs of lines and curves. There are pages for both teachers and students. The student pages ...

• TLF-IDM015447

If you were asked what the biggest number you can think of is, what would you say? Infinity? Well, what about the biggest finite number you can think of? Mathematician Ron Graham came across such a gigantic number in his research that, to capture its massive size, he and his colleagues needed to come up with new methods ...

• TLF-IDM021683

Overcrowding in hospitals is one of the biggest challenges facing our healthcare system . In order to reduce hospital waiting times, the Patient Admission Prediction Tool (PAPT) uses historical data to predict how many patients, and with what kinds of injuries, are expected to arrive at the emergency department each day ...

• TLF-IDM025126

Using an interactive timeline created by the Department of Foreign Affairs and Trade, this Teacher guide provides 12 series of learning experiences that engage students in the analysis and interpretation of data about Australian trade from 1900 to the present day. Students study videos, tables, images and texts in order ...

• TLF-IDM015754

In space there are thousands of human-made objects (satellites and space junk) orbiting Earth. To avoid collision with space debris, satellites are manoeuvred out of its path. Discover how space debris is tracked using lasers, and about accuracy's effects on the lifetime of the satellite. Find out, using trigonometry, the ...