Stage 3 Multiply 2-digits by a single digit number Introduce the grid method for multiplying by single-digits: Link the layout of the grid to an initially: 160 + 24 = 184 Introduce the grid method with children physically making an array to represent the calculation (e.g. make 8 lots of 23 with 10s and 1s place value counters), then translate this to grid method format (see video clip). To do this, children must be able to: Partition numbers into tens and units  Multiply multiples of ten by a single digit (e.g. 20 x 4) using their knowledge of  multiplication facts and place value  Recall and work out multiplication in the 2, 3, 4, 5, 8 and 10 times tables. Work out multiplication facts not known by repeated addition or other taught  mental strategies (e.g. by commutative law, working out near multiples and adjust- ing, using doubling etc.) Strategies to support this are repeated addition using a number line, bead bars and arrays: Key vocabulary: groups of, lots of, times, array, altogether, multiply, count, multiplied by, repeated ad- dition, column, row, commutative, sets of, equal groups, times, _times as big as, once, twice, three times..., partition, grid method, multiple, product, tens, units, value Key skills for multiplication: Recall and use multiplication for the 2, 3, 4, 5, 8 and 10 multiplication tables, and multiply  multiples of 10. Write and calculate number statements using the multiplication tables they know, including 2-digit x  single-digit, drawing upon mental methods, and progressing to reliable written methods. Solve multiplication problems, including missing number problems.  Develop mental strategies using commutativity (e.g. 4 x 12 x 5 = 4 x 5 x 12 = 20 x 12 = 240)  Solve simple problems in contexts, deciding which operations and methods to use.   Develop efficient mental methods to solve a range of problems e.g using commutativity (4 × 12 × 5 = 4 × 5 × 12 = 20 × 12 = 240) and for missing number problems x 5 = 20, 3 x = 18, x = 32 Video clips: partitioning and counters to introduce grid)
Stage 3 Multiply 2-digits by a single digit number Introduce the grid method for multiplying by single-digits: Link the layout of the grid to an initially: 160 + 24 = 184 Introduce the grid method with children physically making an array to represent the calculation (e.g. make 8 lots of 23 with 10s and 1s place value counters), then translate this to grid method format (see video clip). To do this, children must be able to:  Partition numbers into tens and units  Multiply multiples of ten by a single digit (e.g. 20 x 4) using their knowledge of multiplication facts and place value  Recall and work out multiplication in the 2, 3, 4, 5, 8 and 10 times tables.  Work out multiplication facts not known by repeated addition or other taught mental strategies (e.g. by commutative law, working out near multiples and adjust- ing, using doubling etc.) Strategies to support this are repeated addition using a number line, bead bars and arrays: Key vocabulary: groups of, lots of, times, array, altogether, multiply, count, multiplied by, repeated ad- dition, column, row, commutative, sets of, equal groups, times, _times as big as, once, twice, three times..., partition, grid method, multiple, product, tens, units, value Key skills for multiplication:  Recall and use multiplication for the 2, 3, 4, 5, 8 and 10 multiplication tables, and multiply multiples of 10.  Write and calculate number statements using the multiplication tables they know, including 2-digit x single-digit, drawing upon mental methods, and progressing to reliable written methods.  Solve multiplication problems, including missing number problems.  Develop mental strategies using commutativity (e.g. 4 x 12 x 5 = 4 x 5 x 12 = 20 x 12 = 240)  Solve simple problems in contexts, deciding which operations and methods to use.  Develop efficient mental methods to solve a range of problems e.g using commutativity (4 × 12 × 5 = 4 × 5 × 12 = 20 × 12 = 240) and for missing number problems x 5 = 20, 3 x = 18, x = 32 Video clips: partitioning and counters to introduce grid)
Calculation-Policy-November-2014.docx