Programme 5: Addition with partition
Gaining familiarity with patterns when adding tens and hundreds
- Recognising the pattern when adding a single digit to tens
- Partitioning numbers into tens and units and recombining
- Adding multiples of ten to any number
Key vocabulary: add, plus, more, 100 more, total
Resources: arrow cards, 100 square, arrow cards, Can you collect 100 lemons? Resource sheet, die numbered 10,11,12,13,14,15
To partition numbers into tens and units, children need to develop a secure understanding of place value. Provide opportunities for children to gain experience of grouping in tens and units in different contexts using concrete equipment e.g. packing boxes, using structured equipment such as Dienes rods and money. Relate these experiences to recording numbers using hundred grids, place value charts etc. Arrow cards can be a useful resource in supporting children's understanding of partitioning and recombining.
Counting on in tens whole class or group
Children need to be confident with written and spoken numbers to 100. In the mental/oral part of the lesson, encourage them to count on in tens and multiples of ten from any number, indicating the written numerals on a hundred grid. E.g. ask the children to start at 6 and count on in tens to 66. The teacher can record the numbers as the children chant to highlight the pattern in the numbers. Ask the children what they can tell you about the pattern, which number changes and which stays the same and relate this to 100 square.
Counting on in hundreds- whole class or group
Ask the children to count on in 100s with you starting from any number and record the numbers spoken
Can you collect 100 lemons? Resource sheet - individual or paired work
The aim is to collect as close to 100 lemons as possible.
Throw a die numbered 10,11,12,13,14,15 and record the number you have collected in the first square. Throw the die again, record the number thrown in the first lemon oval and put the total in the next square. Continue throwing the die, adding the number thrown each time until you have 100 lemons or as near to 100 lemons as you can get. Have you got 100 lemons exactly? Do you have more or less than 100 lemons? How many?
Children may wish to use the array of lemons as support. Children could write in the numbers or colour in the lemons. Discuss strategies for adding - does it matter whether you add on 10 first or the units first?
This could be adapted by playing it as a game and seeing who can get nearest to 100 without going over.
The activity could be extended by changing the numbers on the dice, aiming to collect 200 lemons, doing the activity in pairs with each person aiming to collect 100 lemons and adding the two totals.
E.g. 2, 102, 202, 302, 402 …. Etc. 45, 145, 245, 345 etc.
Encourage them to look for patterns in the written numerals and note which digits change and which stay the same.