Year 2

We can partition numbers. We can combine numbers.

Year 2 Unit 4

What we are learning:

• Partitioning means knowing what the value of each digit in a number is, so in 25 the 2 stands for two tens, or 20 and the 5 stands for five units or five ‘ones’. Together they make the number 25.
• Before we can partition numbers it is really important that your child can already recognize, read, say and write two-digit and three-digit numbers.
• It is vital that you child has had opportunities to count out loud, and in order from different starting points and to count large numbers of objects. They need to be confident at counting.
• This is now about looking deeper into the patterns and rules in our number system.
• The language of place value is really important – don’t be tempted to ‘make it simpler’ by inventing words of your own.
• Using practical objects will help your child’s understanding
• Remember that whilst this may seem fairly straight forward there are many ‘tricky’ numbers.

ACTIVITY 1: PARTITIONING AND COMBINING NUMBERS USING COINS

ACTIVITY 2: PARTITIONING INTO TENS AND UNITS USING BUNDLES OF STRAWS

Activities you can do at home:

Use straws – count out twenty-seven. Together make into as many bundles of ten as you can, secure these with an elastic band and leave the others (the units/ones). Ask, How many bundles of ten have we got? How many ones? Put them all into a container/box lid and ask, How many are there altogether? Say Two tens and seven units/ones are twenty-seven. Write the number in figures and words. Repeat with other numbers – the making of the bundles is very important at this stage to build the understanding of counting out ten and making them into ‘a ten’.

Start to ‘play’ with the bundles of ten and the units/ones. Ask your child to close their eyes – make a new number using the existing bundles of ten and units/ones – What number have I made? How do you know? Can you make a new number using the bundles of ten and the units/ones? Say and record the number each time in figures and words. Try with bigger numbers. When your child is confident try the ‘teen’ numbers as these are the ‘tricky’ ones.

Turn over number cards – ask your child to make this number using the existing bundles of ten and the units/ones. Ask How do we know how many bundles of ten we need to use? Help your child to make the connection between the digits and the straws – they will probably have noticed this.
Ask Which digit tells us how many (bundles of ten) tens we need? Try showing your child one new number at a time and ask How many tens would you need to get for this number? And for this number…?” As they do this they are starting to be able to visualize the bundles of ten.

To move their thinking forward you can try
– Making a number with the bundles of ten and the units/ones – say 47 and then ask, What number would you have if we added another ten?
Hold the extra ten ready but do not put together with the 47 at this stage. Your child may need to count the bundles of ten and the units/ones – this is fine.
– Remove one of the tens and ask, How many straws are there in the box now? How do you know?
– Try adding/removing more than one ten
– Try adding/removing units/ones
– Take turns in doing this – where your child adds/removes the tens or units and asks you the questions.
Do this with money – 10p coins and 1p coins.
Make 53p (five 10p coins and three 1p coins) and other amounts.
Add another 10p and ask – How much have we got now?
How much would we have if I took away 10p?
What would I need to take away/subtract to have 33p left?

Good questions to ask:

What is the value of this digit in this number?
What does the ‘2’ stand for in 245?
If we have two tens and three units how many have we got altogether?

If your child:

Struggles to identify the value of each digit when partitioning numbers
Practise regularly with bundles of straws so that the value of each digit can be seen