# Castle Douglas Primary and Early Learning and Childcare Centre Activity 1 – Quick Grids

Focus – I can recall my number bonds quickly and accurately and can use multiples of 10 and 100 to create new facts.

Resources – pencil and paper

Draw some 3×3 grids. In the top left draw a + sign. In the other two spaces in the top row and in the left column write 2- or 3-digit multiples of 10 (or alternatively 3- or 4-digit multiples of 100). Finally, fill in the remaining four spaces with the totals, e.g. Activity 2 – Mix and Match

Focus – I can use a range of mental strategies for addition and subtraction for an extended range of numbers – Rounding and adjusting.

Resources – pencil and paper

Copy these 2- and 3-digit numbers: 59, 31, 88, 269, 177, 368 and 406.
Choose pairs of the numbers and find the totals or differences, rounding and adjusting as necessary. Which pair of numbers has a total closest to 450? Which pair has a difference closest to 200? Activity 3 – Darts

Focus – I can use a range of mental strategies for addition and subtraction for an extended range of numbers – Counting on and back.

Resources – pencil and paper

Draw a simple dartboard by drawing a circle split into four or six sectors. In each sector write a 2-digit number, e.g. 46, 58, 68 and 39.
Investigate as many different possible totals as you can that can be scored with three darts on your board. Activity 4 – Make a Kilogram

Focus – I can use a range of mental strategies for addition and subtraction for an extended range of numbers – Complements to 1000.

Resources – food packaging, pencil and paper.

Find food labels showing the masses of different food items, e.g. 440 g, 375 g. Work out how much more of each item would be needed to make 1 kg, i.e. cheese spread weighing 560g would need another 440g. Activity 5 – Pairs

Focus – I can use a range of mental strategies for addition and subtraction for an extended range of numbers – Complements to 1000.

Resources – small pieces of paper and pencil

Write at least six pairs of complements to 1000 on to small pieces of paper, e.g. 472 and 528.
Shuffle them and then match them up again. A ‘Pairs’ game can be played where cards are placed face down, two cards turned over, and pairs kept if they match. Challenge a family member or friend to take part too. Activity 6 – DIY Digits

Focus – I can work out and record addition and subtraction calculations using formal methods for any whole numbers.

Resources – pencil and paper

Make up your own HTU sums using the digits 1–9, e.g. 598, 217, 346.
Find the answer to at least four different addition and subtraction sums.
Challenge – make the largest/smallest possible answers from the digits and design sums that have answers nearest to 400, 300 and 1000. Activity 7 – Brackets

Focus – I can use the rule for the order of operations in calculations.

Resources – pencil and paper

Write the numbers 2, 12, 6 and 3 in this order several times. Then write any signs you choose between the numbers (including brackets) and find as many different answers as you can, e.g.
2 × (12 ÷ 6) × 3 = 12,
(2 × 12) – (6 × 3) = 6,
(2 + 12) ÷ (6 ÷ 3) = 7, etc. Activity 8 – 1 to 20

Focus – I can use the rule for the order of operations in calculations.

Resources – pencil and paper

Make the numbers 1 to 20 using the digits 1, 2, 4 and 8 in any order with any signs (including brackets). All four numbers must be used in each calculation.
e.g. (1+2) x 4 = 12 +8 = 20 