November, 2008 | Maths Blog

Free maths worksheet: subtracting a single digit from a teen

Free subtraction worksheet from mathsblog.co.uk

Here is a maths worksheets concentrating on mental methods of subtracting a single digit from a teen. Much work needs to be done with subtracting from 10 before moving on to this.

There are really two types of question with these which demand different mental approaches.

The first type: eg 17 – 6 where it is easy to subtract the 6 from the 7 leaving 11. The tens are not affected.

The second type: eg 16 – 8 where the 8 is larger than the 6 is harder.

One method is add on from 8 to 10 (2 which has to be held ‘in your head’) and then count on from 10 to 16 which is easy (6) and add the two together to get 8. It is surprising how often we add on to do a subtraction sum!

A different approach is to know your doubles: knowing double 8 is 16 means the answer has to be 8.

subtract from teen p1

Kipper’s Toybox by Mick Inkpen

Kipper’s Toybox by Mick Inkpen
Kipper’s Toybox (Kipper)

If you are looking for a great book to help with early counting then Kipper’s Toybox is a must.
Kipper is a cheeky little puppy who is concerned that somebody or something is nibbling a hole in his toybox and that his toys might not be safe. But, the trouble is, that every time he counts them he gets a different number. To make it easier to count he lines them up.
Then, one night, one of his toys appears to have come to life!
Colourful illustrations and a great story line makes this a fabulous book for all 3+ children.
It could also be used as the basis of a great counting activity at home. Use a box with 5 toys, count them as you put them in. Take one away, count them again and see if your child can spot which one is missing.

News: Memory 4 Teachers

News from mathsblog.co.uk: memory 4 teachers!

I know that a lot of the readers of this blog are teachers, so, if you are a teacher in the UK you might have heard about the Memory 4 Teachers project. The project has been developed, in association with LEAs and Teacher Unions, to support teachers and educators by funding the provision of 750,000 USB memory sticks across the UK – yes, that includes Scotland and Wales!

The sticks have a capacity of 2 GB but are not just empty memory. They will include some great free educational resources and access to some of the best educational sites; from what I have heard the content is going to be really worthwhile. One interesting point is that the memory sticks come with a lifetime guarantee which means that teachers will be able to use the sticks forever.
I believe that the launch of Memory 4 Teachers is due to coincide with the Bett Exhibition in early January.
It is easy for a teacher to register for his/her memory sticks. Just click the link below and complete the online form.
Teacher sign up for memory 4 teachers

Free maths worksheets: standard written methods of subtraction

Standard written methods of subtraction worksheets from mathsblog.co.uk

Written methods of subtraction often cause problems for children and it is important to state that a good mental knowledge of numbers is essential if written methods are going to be grasped successfully.

In the UK the standard method of subtraction is often known as decomposition. It should be used when numbers are too large or too awkward to subtract mentally. Remember: mental methods should be the first resort!

The first page of the link shows how the decomposition method works, and is probably the one you learnt at school, although there are other, equally valid methods of subtraction.

Standard written subtraction 1

Number Day 2008

Mathsblog supports Number Day 2008 December 4th.

Number Day 2008 is just a month away! Teachers, if your school is not already taking part then why not download your free Number Day Resource Pack? You should already have been sent a pack through the post. Parents: why not ask your school to take part?
The Number Day Resource Pack contains everything your school needs for a successful event, and the money your school raises will help make a real difference to children’s lives. Continue reading “Number Day 2008”

Free Y6 maths worksheet: reflective symmetry

Free Y6 maths worksheet: reflective symmetry from mathsblog.co.uk

By the end of year 6 children should know and be able to read, write and use the following quite tricky words:

Mirror line, line of symmetry, line symmetry, symmetrical, reflect, reflection, translation, axis of symmetry, reflective symmetry.

Also they should be able to test for symmetry using a mirror and by folding.

Children should be able to sketch the reflection of a simple shape in a mirror line where none or only some of the edges of the shape are parallel or perpendicular to the mirror line.

This might seem easy, but actually prove problematic to many children. A small mirror is a great help with this and children are supplied with one in their SAT tests if such a question comes up – and they do seem to be very popular.

Year 6 maths worksheet: reflective symmetry