Mathematics / Year 3 / Number and Algebra / Number and place value

Curriculum content descriptions

Recall addition facts for single-digit numbers and related subtraction facts to develop increasingly efficient mental strategies for computation (ACMNA055)

Elaborations
  • recognising that certain single-digit number combinations always result in the same answer for addition and subtraction, and using this knowledge for addition and subtraction of larger numbers
  • combining knowledge of addition and subtraction facts and partitioning to aid computation (for example 57 + 19 = 57 + 20 – 1)
General capabilities
  • Numeracy Numeracy
ScOT terms

Mental arithmetic,  Subtraction,  Addition,  Associativity

Interactive

Sites2See – number for primary

Selected links to a range of interactive online resources for the study of number in Foundation to Year 6 Mathematics.

Interactive

The difference bar: generate easy subtractions

Learn how to split up numbers in your head. Use a linear partitioning tool to help find the difference between pairs of two-digit numbers such as 25 and 34. In these examples, the difference is always less than ten. Split the numbers into parts that are easy to work with, work out each part and then solve the original calculation.

Interactive

Sushi monster - iTunes app

The Sushi monster needs to be fed the correct sum or product. Choose to play the addition or multipliaction game. In the addition game select the two numbers that make the target sum. In the multipication game select two numbers to make the target product. This game has several levels. Free when reviewed on 12/5/2015.

Interactive

MoneySmart: Pay the price

This learning object helps students to recognise Australian currency through a supermarket shopping scenario which requires simple transactions. Students match item value with the correct coin and note combinations. The learning object has three different levels working through matching item value to: two single coins, ...

Interactive

Summing Decimals

An interactive resource in which students learn how to add and subtract numbers that have up to two decimal places.

Interactive

MoneySmart: Money match

This learning object helps students to recognise Australian currency through matching notes and coins. Students match different combinations of notes and coins to arrive at the same value in multiple ways. The learning object has four different levels working through matching: same coins, coins of different values, coins ...

Interactive

Sites2See: Patterns and Algebra

Selected links to a range of interactive online resources for the study of patterns and algebra in Foundation to Year 6 Mathematics.

Interactive

The difference bar: go figure

This tutorial is suitable for use with a screen reader. It explains how to split up numbers in your head when finding the difference between two numbers such as 26 and 73. Work through sample questions and instructions explaining how to use linear partitioning techniques. Find the difference between pairs of numbers. Split ...

Interactive

Divide it up: puppies

Use a dividing tool to make equal shares of biscuits and toys in a pet shop. For example, share 34 biscuits equally between 6 puppies. Predict how many items each puppy will get, or how many packets can be filled. Check your prediction. Decide what to do with any leftovers. Complete a sentence describing the number operations.

Interactive

The number partner: go figure

This tutorial is suitable for use with a screen reader. It explains strategies for breaking up numbers into pairs of smaller numbers, eg 15 = 11 + 4. Work through examples of whole number pairs and sample questions. Apply these principles to solve additions or subtractions.

Interactive

Wishball: hundreds

Test your understanding of place value with three-digit numbers. Start with a three-digit whole number such as 507. A spinner provides a randomly generated digit. Choose its place value and add it to (or subtract it from) your starting number. Work towards a given target number, say 539, using other digits. You can choose ...

Interactive

The array

Use an array-building tool to help solve multiplications. Explore strategies to break up multiplications. Create and solve easy multiplications such as 9x3. Examine relationships between rows, columns and areas in arrays.

Interactive

Circus towers: square stacks

Work out how many acrobats are needed to form square-shaped human towers. Start by building a square tower with four acrobats: two acrobats in the base layer and two acrobats standing on their shoulders. Examine a table and graph of the total number of acrobats in the towers. Predict the number of acrobats needed to build ...

Interactive

Divide it up: grouping tool

Use a dividing tool to make equal shares of stationery such as pens, pencils or crayons. Complete a sentence describing a number operation. For example, pack 24 crayons into packets of 5. Predict how many packets are needed and identify how many items are left over.

Interactive

Musical number patterns: musical times

Make some music by building up rhythms from four instruments. Make a counting rule that matches a pattern on a number line. Select the start number and then select a number to count by. For example, describe a sound pattern where a saxophone waits on the first note, and then plays on every eighth note. Add a second number ...

Interactive

Wishball: whole numbers

Test your understanding of decimal place value with whole numbers. Receive a starting number, such as 3786, and work towards turning it into a target number, such as 7664. Spin a random digit, choose its decimal place value and decide whether to add or subtract the random digit from your starting number. You can use a 'Wishball' ...

Interactive

The multiplier: go figure

This tutorial is suitable for use with a screen reader. It explains strategies for solving complex multiplications in your head such as 22x38. Work through sample questions and instructions explaining how to use partitioning techniques. Solve multiplications by breaking them up into parts that are easy to work with, use ...

Interactive

Cassowary ecology quiz

Explore facts about the life of cassowaries: physical characteristics; diet; habitat; life cycles; and locations. Interact with graphs to see how much people can help cassowaries. Work through ecology notes and resources. Answer questions as you go; express your answers as fractions. This learning object is one in a series ...

Interactive

The take-away bar: go figure

This tutorial is suitable for use with a screen reader. It explains strategies for solving subtractions in your head such as 87-39. Work through sample questions and instructions explaining how to use linear partitioning techniques. Solve subtractions by breaking them up into parts that are easy to work with, work out each ...

Interactive

Wishball challenge: hundreds

Challenge your understanding of place value in whole numbers up to 999. Receive a starting number, such as 328, and work towards turning it into a target number, such as 177, within 20 turns. Spin a random digit, choose its decimal place value and use the given operation (either addition or subtraction) on your starting ...