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Resource of the Week: Make 18

Here is a worksheet that makes children think a little bit more. It shows a number sentence with two numbers that total 18. It asks what the two numbers could be.

The first thing to look for with this is children who use a logical or methodical approach. Usually children will write down the first answer that comes into their heads. That is why I have provided two blank number sentences at the top of the page. However, once they have done this they should start to revise their thinking and try to approach the task in an order so that they will know when they have reached all the possible answers.

This activity can be extended using different numbers eg 19 or 20 and it is a useful exercise in helping children learn these pairs of numbers ‘off by heart’.

It can also be extended by allowing halves, which makes it quite a bit harder.

This can be found in the year 3 resources.

Addition number sentences: add 18

Resource of the week: division as sharing

Our resource of the week this week looks at early understanding of division. Division is usually the hardest of the four rules for children to learn, but in the early stages it is quite straightforward. Children often come across division for the first time when sharing, usually between two. The key concept,of course, is that the sharing is done equally. So, for example, 6 sweets shared between 2 children implies that the sharing is equal and they both receive the same number.

By far the best way to practice sharing is to use practical apparatus or use real life situations: e.g. share the strawberries equally between two, share or deal the cards equally etc. Usually this is done on a ‘one for you and one for me’ type process until there are none left. This maths worksheet replicates a practical situation, with the ultimate aim that children begin to remember the answers, which, of course are the inverse of multiplication.

Be careful when sharing that it is not always done into two, as some children begin to think that to share something it can always be divided by 2 and no other number.

Division as sharing (pg 1)

Resource of the Week: Maths SAT questions

For anyone in Year 6 the Maths SAT tests will be coming up before too long! Don’t forget that we have a whole section of past questions and answers, including great explanations of the best ways to approach each question. Invaluable help to achieve those higher levels!

This week I am highlighting are two questions from the Maths SAT Paper 2011 Paper B. The first involves equivalent fractions and the second angles and shape.

The answer to Question 8. 3/4
One mark awarded for a correct answer.
Equivalent fractions accepted as is 0.75.
Suggested method:
This question is another reading a number line problem and if children can count in quarters it is an easy mark. Firstly, it has to be recognised that the number line is showing quarters (1/2 is equivalent to 2/4 and 1 is equivalent to 4/4) making the missing number 3/4.

The answer to Question 9. A and D.
One mark awarded for a correct answer.
The letters can be given in either order. Both need to be given with no incorrect angles added.
Suggested method:
Answering this question correctly depends on 3 things:
Firstly, a recognition of the conventions for labelling angles, using the arc.
Secondly, a knowledge that an obtuse angle is larger than 90 degrees but less than 180 degrees.
If either of these are unknown it becomes purely a guessing game. (Some children do think that the angle depends on the length of the lines rather than a measure of turn.)

Thirdly, if these are known, then the obtuse angles still need to be recognised. One way to do this is to slide a right angle (eg a corner of a piece of paper) into the angle to see whether it is smaller or larger.

Why not visit ks2-maths-sats.co.uk for free SATs papers and a great SAT revision programme?

Questions 8 and 9 from SAT Paper B 2011

Questions 8 and 9 answers and suggested method 2011 Paper B

Resource of the Week: Christmas maths activities

It’s getting very close to Christmas now and with many activities going on in school why not try a little Christmas maths as well?

This page is quite an open ended challenge as all the possible combinations of presents need to be found. There are four items with prices; a set of beads for £2, a box of chocolates for £3, a bag for £5 and a bottle of perfume for £7.

The task is to find as many different combinations of presents that can be bought for up to £10. The key here is that the whole £10 does not have to be spent.

So 3 sets of beads and a box of chocolates is one possibility, costing £9 in total.

As usual, look for well a well organised logical approach.

This page can be found in the year 4 Using and Applying Maths category.

Christmas presents

Resource of the week: scalene triangles

This week we take another look at types of triangle. A lot of work is done on triangles in Primary Schools and by year 5 and 6 most children are familiar with the properties of right angled triangles, equilateral triangles and isosceles triangles. An equilateral triangle has all three sides equal and all three angles equal; an isosceles triangle has two equal sides and two equal angles. However, fewer children know about the scalene triangle. A scalene triangle is one which has no sides the same length and no equal angles. Right angled triangles could also be scalene if all the sides are different lengths.

Thanks to MathSphere Ltd for this worksheet: and there are many more similar pages, both on their site and part of the ‘It’s All Figured Out’ CD.

This page can be found on the blog in the Year 5 section under Shape.

Go to our year 5 shape resources

Bonfire Night Worksheets

It’s always nice to have something topical to use as part of the maths curriculum. Today I would like to point you to a page on percentages, linked to the theme of bonfire night, or fireworks, suitable for Year 6 children who are learning about how to work out percentages.

Four different kinds of fireworks are on sale, with 20% off. The questions involve working out how much the boxes cost and how much in the way of savings can be made.

Finding 20% is relatively straightforward if done in two parts:

first find 10% by dividing by 2

find 20% by doubling the answer.

You can find this page in my Year 6, Understanding Number section.

Thanks to urbrainy.com for letting me publish this page. There are more bonfire night pages on their site, which you can trial free of charge at urbrainy.com

Bonfire night percentages

Resource of the Week: Subtraction of money

The standard written method of subtraction is usually used when adding amounts of money, but it can prove quite tricky as it involves decimals. It is important to lay the question out in the standard way, even if it is shown horizontally or just as a written problem and most importantly, to keep the decimal points in a line. if using squared paper it is best to puit the decimal point on the line rather than in a square.

Watch out when there is a zero on the top line as many children go for the easy option and say ‘nought take away 3 is 3’ rather than going through the carrying process.

This is just one of our series on subtracting money.

Standard money subtraction: page 2

Resource of the Week: Find tenths and hundredths

$find fractions 2$ This week we take a look at a worksheet on the relationship between fractions and division. It is important that children understand that finding one half of a number is equivalent to dividing by 2, that finding one tenth of a number is the same as dividing the number by 10 and to find one hundredth is equivalent to dividing by 100. Plenty of practice is needed with this before children go on to find, for example, two tenths, or three hundredths of numbers.

Most of these questions should be calculated mentally, although rough jottings may help. The second set of questions could cause a few problems. For example: ‘What fraction of a £1 is 20 ?’ requires a couple of steps:

Firstly convert the pound to pence £1 = 100p

Secondly write the fraction as 20 out of 100 or 20/100

Thirdly simplify to 2/10 and then 1/5.

Find fractions of numbers (p2)

Resource of the week: year 5 square numbers

This is just one of a short series of square number maths worksheets for Year 5. It is an interesting and worthwhile exercise asking children to see if they can make a square out of 10 or 12 smaller squares (not overlapping etc) using plastic or card squares. Rectangles are possible, but not squares.

They can then be asked to find which numbers can be made into a square. This can be done either with smaller squares or as dots in an array.

There are several ways that questions involving square numbers can be phrased, including:

What is 4 squared?

What is the square of 4?

What number multiplied by itself makes 16?

Square numbers 2

Resource of the Week: half way between

This week I am highlighting a page which, on the face of it this looks quite a simple task, but many children (and adults) find very tricky. The page is on how to work out what half way between two numbers is. Often there is a lot of ‘trial and improvement’ going on in people’s heads as they guess their way towards finding half way.

Two methods make the task fairly straightforward.

For method one a number line is very useful to start with. Put a finger of the left hand on the first (lower) number shown on the number line and a finger of the right hand on the second number. Then move the left hand finger one place to the right and the right hand finger one place to the left. Repeat this until the two fingers meet – that is your half way number.

The second way of finding half way involves two steps:

step 1: add the two numbers.

step 2: halve the answer.

This is the better method as it works for all numbers, not just those shown on the number line.

This page can be found in our Year 3, Counting and Number section

Half way between_(1)