Year 2: Place value
Focused learning objectives Starter: compare and order numbers from 0 up to 100 Main: Recognise the place value (quantity value) of each digit in a two-digit number (tens, ones) |
Success criteria Read two-digit numbers Know that the numbers are in order on a number line or in a hundred grid and use these to help order numbers Know which digit is the tens and which digit is the ones in a given two-digit number Use practical resources and/or images to represent the number of tens and ones in a given two-digit number |
Vocabulary
tens, ones, digit, two-digit number, in order, between
Resources
Starter
Number card for every child (a selection of numbers between 0 and 100 appropriate for the class)
Set of pre-prepared ‘selection’ cards and one blank card in a bag, e.g.
Main
Individual whiteboards and pens
Bags of balloons with ten in each bag (or the lesson context could be changed to another resource that is packaged in tens)
A set of numbers for each pair of children to use during the main activity (these can be differentiated)
Timing 10/15 minutes
Timing 30 minutes |
Starter Take the children out on to the playground. Altogether, rehearse counting in tens and counting in ones from a multiple of ten, e.g. Count in tens from 0 to 100 Count in tens from 30 to 80 Count in ones from 30 to 42
Main Introduce the context for the main part of the lesson. Mr Bumble owns a balloon shop. He sells balloons individually and in packs of ten. Explain that we are going to help him with his customers today. The first customer wants 32 balloons. Ask the children in pairs to discuss how many bags and how many individual balloons Mr Bumble needs to give the customer. Draw three bags and write ‘10’ on each bag and then draw two small balloons and write ‘1’ on each balloon. Count in tens and write ‘30’ underneath the packets and count in ones and write ‘2’ underneath the individual balloons. Now record 30 + 2 = 32: |
Now give each child a number card so each child has a different number. Explain that you are going to ask some children to get in order. Ask the children to talk to the person next to them to agree what ‘in order’ means and take feedback. Now choose five children and ask them to see if they can get in order. Ask all the children to watch carefully to see whether they agree. When everyone agrees that the five numbers are correctly placed, choose another five children and ask them to position themselves amongst the numbers already there so that all the numbers are in the right order. Continue to add five children to the line until all numbers have been placed.
Now, using the bag of cards, ask a child to take out one of the cards and read out what is written. The children holding numbers that fit the selection take one step forward. Continue to take out cards from the bag for a few minutes, asking (some) children to justify their step forward. Has everyone taken at least one step forward? If not, ask children to think of what could be written on a card to allow them to move forward. Write this on a card and read it out.
Support
Number lines from 0 to 100 or hundred squares could be available for children to use and check against.
Challenge
What could you write on a selection card that would mean:
no one steps forward?
everyone steps forward?
Now draw two bags and five individual balloons. Ask the children how many balloons this customer has ordered. On whiteboards see if the children can write this calculation (20 + 5 = 25). Repeat the above as necessary and include a ‘teens’ number. Finally ask the children to close their eyes and try to visualise the number of packets of balloons and individual balloons Mr Bumble will give to the next customer, who wants 43 balloons. Ask the children to draw on their whiteboards what they were seeing in their heads. If there are variations in what the children have drawn, encourage these children to come to the front so you can discuss and show the rest of the class what they have drawn.
Explain that they are now going to work in pairs to help Mr Bumble in his shop. They will take it in turns to be Mr Bumble and the customer. Give each pair a set of numbers you would like them to select from during this activity. The customer will pick one of these numbers and ask for that number of balloons. Mr Bumble will then draw and record the number of balloons the customer will receive (using images and the calculation as above). The customer will try to visualise the number of packets of balloons and individual balloons. The customer must always check that Mr Bumble hasn’t made a mistake!
Simplify
Ask the children to count the balloons practically into packets of ten for Mr Bumble. Focus on the teens numbers, e.g. for 13 encourage the children to put ten balloons into a packet and then put three single balloons with it. Encourage the children to describe what they have done to make the required number of balloons.
Extend
Ask the children to work in pairs. Provide them with a sequence of numbers (of balloons) which can be made by adding/removing either tens or ones, e.g. 23 balloons, 27 balloons, 47 balloons, 17 balloons, 12 balloons, 52 balloons, etc.
Explain that there is a difficult customer who keeps changing his mind about how many balloons he wants. Ask them to pick the first number (e.g. 23) and each draw the correct number of packets of balloons and individual balloons. After they have checked each other’s drawings they look at the next one on the list (e.g. 27). The customer has changed his mind and now wants a different number of balloons. How can they change their drawing to represent 27? The children must explain to each other what they have done and why, e.g ‘I already had 20 balloons and three balloons, which is 23, so I needed to add another four balloons to give me 27’.
This activity could be recorded in their books or on an activity sheet, with the different numbers shown. This means that changes made are recorded. Try to encourage the children to decide how they might record the changes so that anyone reading their work would be able to follow what they had done.
Timing 10 minutes |
Plenary/conclusion Write the numbers 23 and 32 on the board. Ask what is the same and what is different about these two numbers? Ask the children to share their ideas with a partner before sharing ideas as a whole class. Ask further questions to probe their understanding, e.g. How many packets of balloons would I need for 23 balloons? For 32 balloons? Would you rather be given 23 sweets or 32 sweets? Why? Would you rather have 23 days or 32 days left until your birthday? Why? What else can you tell me about number 23? |
Assessment opportunities
Whilst they are working, ask children questions such as these. You might want to focus on those children whose level of understanding you are unsure about. These might be children you think are unclear or children whose thinking you can extend.
Can you explain to my why the picture you’ve drawn shows 43 balloons?
This picture shows three bags and four balloons. Would this be right for a customer who asked for 43 balloons? Why?
This picture shows 43 balloons. If a customer wanted 63 balloons, how many more do you need to give the customer?
What if a customer wanted 48 balloons but Mr Bumble only has two packets left but lots of single balloons? Can he give the customer what he has asked for? How could he do this? Could we write a number sentence to show what this would look like?
Potential challenges
There are some common errors and misconceptions to be aware of when teaching place value.
The ‘teens’ numbers can be particularly problematic for children. One potential issue is that some of the teens numbers can sound very similar to the tens numbers and so, for example, children may struggle to distinguish between numbers such as forty and fourteen. It is therefore important that both you and the children are very clear and precise when pronouncing numbers.
Recording numbers can also lead to misconceptions and again it is the ‘teens’ numbers that can cause difficulty. For most two-digit numbers we refer to the tens digit first when saying and recording the number; however, when we say a ‘teens’ number we refer to the ones digit first. It is therefore not uncommon for children to record numbers such as ‘fourteen’ as 41. Children also need to appreciate the compact way in which we write all numbers. To some children it is completely logical to write twenty-five as 205 as this matches the way we say the number.
Make sure that you never read a number by just sayings its digits. For example, the number 25 should always be read as ‘twenty-five’ and not ‘two five’.
Ways the lesson could be adapted
The school hall could be used for the starter instead of the playground (if another class is using it for PE you might be able to have the first few minutes while they get changed).
Other equipment and contexts could be used instead of the balloons. You could use: 10p and 1p coins to make given amounts;
art straws tied together in bundles of ten;
everyday items that come in packs of ten;
structured place value equipment such as place value (arrow) cards and tens and ones materials.