EY

KS1

KS2

AS

CP

Unit A2 Lesson n1

Unit A2 Lesson 2

Sweet estimating

Rabbit rounding up

• Estimate up to about 100 objects

• Round any two-digit number to the nearest 10

Work in pairs. Take turns to point out a sweets pattern to your partner. Ask your partner to guess the number of sweets. Now count the actual number of sweets. Find the best way to guess.

How far has each rabbit travelled? Write your answer to the nearest 10 metres.

a

e

d

c

b

f metres

30

40

50

1 Round each length to the nearest 10 metres. G a

b

c

d

e

The number on the label shows how many sweets are in a full jar. Estimate how many sweets are in each jar. a

b

c

d

100

80

60

150

17 m

93 m

f

g

h

70

100

90

120

6m

2 Round each distance to the nearest 10 metres. G b

a e

22 m

45 m

Collins New Primary Maths

Age 4-11

d

c Park 53 m

Beach 35 m

Library 18 m

e Museum 96 m

Toilets 104 m

The lengths of the fish have been rounded to the nearest 10 cm.Write five possible lengths for each fish.

A game for 2 or 3 players. G Take it in turns to pick up a handful of cubes and drop them on the sheet of paper. G Each player then estimates the number of cubes on the paper. G Count the cubes. G The player with the closest estimate wins one point.

You need: G cubes

c

a 10 cm

G paper

70 cm

b d

100 cm 40 cm 5

4

Sample pa Sample page ge fro from m Pupi P upill Book Book 3B Pupil

Unit B1

B1 Securing number facts, understanding shapes L5

Lesson

5

Subtraction number facts to 5

Objective

Pupil activities Activity Book 1A Juggle the jugs Page 16

• Derive and recall all addition facts for totals to at least 5; work out the corresponding subtraction facts

Vocabulary zero, one, two…; count on/back /to/from; less; how many less than?; take away; leaves

Oral and mental starter

child works out the answers to their calculations. When each child has done this, they swap calculations and work out the other calculations.When each child has done this, they pool the cards, and compare answers.

Choose an activity from Strand 2 or Strand 3 or Strand 4 Software Teach B1 L5

Main teaching 1

• •

Display the 0–10 number line with the frog at 3 and the snail at 0.

Show this to the children, as you say: The frog was on number three, she made two jumps back, and she landed on number one.

• • •

Write and say: 3 – 2 = 1.

After each calculation, ask the class to identify the missing sign and choose a child to write in the missing mathematical symbol.

Next, move the frog to 3 on the number line, and the snail to 1, and say: The frog is at number three, but has to jump to number one.

• • • • • • • • •

Resources RCMs 24 and 25, Subtraction number facts to five with missing numbers (per pair); pencil and paper (per child)

What to do Children divide the calculation cards evenly amongst themselves. Each

Resources 0–10 number line (per child); counter (per child); 1–6 die (per child); pencil and paper (per child)

What to do Children place their counter on six on the number line. They roll the

Say: The frog is going to make two jumps, back towards the snail. Ask: Which number will she land on? (1)

die, e.g. 2, and move their counter back that number of spaces. They record this as a subtraction calculation, i.e. 6 – 2 = 4. They then put the counter back on six and repeat several times. Variation: children place the counter on seven, eight, nine or ten.

Repeat above several times writing each complete calculation on the board. Now repeat above, but this time omitting either the subtraction or equals sign from the written calculations.

Plenary 2

3

Write 3 –  = 1.

• Display the four subtraction calculations. • Ask individual children to offer the answers. • Display the four subtraction calculations for six, this time including

the second number.

• Ask individual children to offer the answers. Encourage the children to explain their thinking.

Say: Three and how many jumps back to reach one? (2)

Ask: What is the answer to this number sentence? How do you know? How did you work it out? Did anyone work it out in a different way?

Count and show the frog making two jumps back. Write and say: 3 – 2 = 1. One is two less than three. Write 4 –  = 2.

• Can you use these numbers and signs to make a subtraction calculation? 4 3 1 – = • Can we start the number sentence with the smallest number? Why not? • If you know that 4 – 1 = 3, what other subtraction calculation do you know? • What if we change the – to a +? What number sentences can we write now?

Ask: Four and how many less will leave two? (2) Count and show the frog making two jumps back. Write and say: 4 – 2 = 2. Two less than four is two. Repeat above several times, using different shapes to stand for the unknown number. Start the subtraction calculations for three, (e.g. 3 – 2, 3 – 1), before starting with larger numbers (e.g. 4 – 0, 4 – 3, 5 – 1, etc.).

Common difficulties and remediation Children sometimes find subtraction facts to be abstract, and may remember them without really understanding them. If they have not remembered them accurately then, without understanding the processes involved, they will find it hard to see their mistakes. Explain the subtraction facts using concrete examples to illustrate each calculation. Relate these where possible to the children’s everyday situations to make their learning more meaningful.

88

89

Sample S Sam ple l page ffrom rom Teach T Teacher’s her’’s Guid G Guide ide 1

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Collins Primary Catalogue 2013
Collins Primary Catalogue 2013

Up to date resources for teaching and learning, helping motivate children across the ability range - from strugglers to the most able.