Calculations

38-39 Rapid recall of addition and subtraction facts

Derive quickly or continue to derive quickly:decimals that total 1 (e.g. 0.2 + 0.8) or 10 (e.g. 6.2 + 3.8);all two-digit pairs that total 100 (e.g. 43 + 57);all pairs of multiples of 50 with a total of 1000 (e.g. 350 + 650). (p.39)

Number bonds - 100 or set your own target bond.

Ambleside 'NumberBond Machine'

40-47 Mental calculation strategies (+ and -)

Find differences by counting up through next multiple of 10, 100 or 1000, e.g. calculate mentally a difference such as 8006 - 2993. (p.41)
Partition into H, T and U, adding the most significant digits first. (p.41)
Identify near doubles, such as 1.5 + 1.6. (p.41)
Add or subtract the nearest multiple of 10 or 100, then adjust. (p.41)
Develop further the relationship between addition and subtraction. (p.43)
Add several numbers (e.g. four or five single digits, or multiples of 10 such as 40 + 50 + 80). (p.43)
Use known number facts and place value for mental addition and subtraction (e.g. 470 + 380, 810 - 380, 7.4 + 9.8, 9.2 - 8.6). (p.45,47)	Addition pyramid, possible extention of rearranging numbers to create largest total	Primary Resources 'Bricks 2'

48-51 Pencil and paper procedures (+ and -)

Use informal pencil and paper methods to support, record or explain additions and subtractions. Extend written methods to: column addition/subtraction of two integers less than 10000; addition of more than two integers less than 10000;addition or subtraction of a pair of decimal fractions, both with one or both with two decimal places (e.g. £29.78 + £53.34). (p.49,51)

52-57 Understanding multiplication and division

Understand the effect of and relationships between the four operations, and the principles (not the names) of the arithmetic laws as they apply to multiplication. Begin to use brackets. (p.53,55)
Begin to express a quotient as a fraction, or as a decimal when dividing a whole number by 2, 4, 5 or 10, or when dividing £.p.Round up or down after division, depending on the context. (p.57)

58-59 Rapid recall of multiplication and division facts

Know by heart all multiplication facts up to 10 × 10. (p.59)	Use as a physical counting stick. Very easy to cover / uncover numbers / multiples Primary Resources 'Counting Stick' Practice at identifying multiplication facts in rather fun way. Children individually or on whiteboard during mental and oral starter Primary Resources Moon Maths Activity allowing practice of recognition of chosen multiples. Short starter or short individual practice. Grid Club 'Alien Tables'
Derive quickly or continue to derive quickly:division facts corresponding to tables up to 10 × 10;doubles of all whole numbers 1 to 100 (e.g. 78 × 2);doubles of multiples of 10 to 1000 (e.g. 670 × 2);doubles of multiples of 100 to 10000 (e.g. 6500 × 2);and the corresponding halves. (p.59)

60-65 Mental calulation strategies (mult and div)

Use doubling or halving, starting from known facts. For example:double/halve any two-digit number by doubling/halving the tens first;double one number and halve the other;to multiply by 25, multiply by 100 then divide by 4;find the ×16 table facts by doubling the ×8 table;find sixths by halving thirds. (p.61)
Use factors (e.g. 8 × 12 = 8 × 4 × 3). (p.61)
Use closely related facts (e.g. multiply by 19 or 21 by multiplying by 20 and adjusting; develop the ×12 table from the ×10 and ×2 tables). (p.63)
Partition (e.g. 47 × 6 = (40 × 6) + (7 × 6)). (p.63)
Use the relationship between multiplication and division. (p.63)
Use known facts and place value to multiply and divide mentally. (p.65)

66-69 Pencil and paper procedures (mult and div)

Approximate first. Use informal pencil and paper methods to support, record or explain multiplications and divisions. Extend written methods to:short multiplication of HTU or U.t by U; long multiplication of TU by TU;short division of HTU by U (with integer remainder). (p.67,69)

70-71 Checking results of calculations

Develop calculator skills and use a calculator effectively. (p.71)

Online Calculator

Ambleside 'Online Calculator'

72-73 Checking results of calculations

Check with the inverse operation when using a calculator. (p.73)
Check the sum of several numbers by adding in the reverse order. (p.73)
Check with an equivalent calculation. (p.72)
Estimate by approximating (round to nearest 10 or 100),then check result. (p.73)
Use knowledge of sums and differences of odd/even numbers. (p.73)

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