Multiplication — Tasmanian Year 4 Maths
Multiplication facts for 6, 7, 8 and 9, multiplying by 10 and 100, and the split strategy for two-digit numbers. Three subtopics and 60 questions with worked solutions, aligned to AC9M4A02, AC9M4N05 and AC9M4N06.
Multiplication in Tasmanian Year 4
This topic moves multiplication from counting to quick recall and smart strategies. Students build the harder facts for 6, 7, 8 and 9 from ones they already know, see how place value works when a number is multiplied by 10 or 100, and use the split strategy to multiply a two-digit number by a one-digit number.
The three subtopics are Multiplication Facts: 6, 7, 8 and 9, Multiply by 10 and 100, and Distributive (Split) Strategy for Multiplication. Multiplication is one of the 20 topics in Tasmanian Year 4 Maths and draws on the Number and Algebra strands. It comes under Australian Curriculum codes AC9M4A02 (recalling facts and using them in mental strategies), AC9M4N05 (multiplying by 10 and 100 using place value) and AC9M4N06 (efficient calculation strategies). These skills lead into Division and into multiplying larger numbers.
Subtopics
Multiplication: common questions
What is the best way to learn the 6, 7, 8 and 9 times tables?
Build them from facts children already know. The eights are double the fours, so \(8 \times 4\) is double \(4 \times 4 = 16\), which is \(32\). The nines are ten groups take away one group: \(9 \times 4 = 40 - 4 = 36\). Turnaround facts, such as \(7 \times 6 = 6 \times 7\), halve the number of facts to learn.
Why isn't multiplying by 10 just adding a zero?
Every digit shifts one place left, while the zero holds the empty ones place: \(37 \times 10 = 370\). For \(\times 100\) the digits move two places, so \(37 \times 100 = 3700\). Thinking in place value, not adding zeros, still works later with decimals.
What is the split strategy?
Split the two-digit number into tens and ones, multiply each part, then add: \(4 \times 37 = 4 \times 30 + 4 \times 7 = 120 + 28 = 148\). An area model, a rectangle cut into two parts, shows why it works.
What mistakes do children make, and how can they practise at home?
A common slip in the split strategy is multiplying only the tens and then just adding the ones. At home, practise a few facts each day, look for arrays in egg cartons and muffin trays, and ask for the matching division fact as well.
Which curriculum codes cover Multiplication in Tasmanian Year 4?
Australian Curriculum v9 code AC9M4A02 covers quick recall of the times tables to 10 × 10, used in mental strategies, AC9M4N05 covers multiplying by 10 and 100 using place value, and AC9M4N06 covers efficient strategies such as the split strategy.