do now new learning · the cards. for example, can they use a set of consecutive numbers? or...

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Year 1 Unit 13: Adding and subtracting within 100 Lesson 9: Applying addition and subtraction strategies

Key learning: To solve problems in a context using addition and subtraction

Lesson overview This is a lesson for pupils to have as many opportunities to practise their addition and subtraction strategies in a meaningful and purposeful context. Throughout the lesson, teachers should consider the strategies pupils are using to solve calculations, ensuring they are reinforcing and consolidating the strategies covered within Year 1.

Possible misconceptions When first encountering the

superhero skills, it may be necessary to explain what some of the attributes mean. During application, pupils may forget to use the addition and subtraction strategies that have been practised. They may also become confused due to the fact that both addition and subtraction be used to successfully solve the problem. Teachers can use mini plenaries to ensure there is a secure understanding, and should use professional judgement on whether to add further constraints to the task to structure learning. Key vocabulary subtract, add, total, value Sentence structures _ subtract _ is equal to _. _ plus __ is equal to __. Resources bead string part-whole model task sheets number lines By the end of this lesson ALL pupils must be able to: Apply addition and subtraction with confidence to solve problems.

Do Now

Solving missing number problems

Pupils to find the missing number in a number of positions within an equation.

New Learning

New superhero cards

Introduce the context to the pupils:

MM Comics are producing their own range of superheroes, but they need your

help.

Explain that each superhero has a card to show their skills. Their total skills

must add up to 20. Show an example of a superhero card and let pupils explore

how it works/ask questions for further clarification. Show one example and

model adding all of the values, totalling 20. Show the next slide with a mistake.

Can you find a mistake here? Explain how you know…

Can you fix the problem?

Establish that we know the superhero cards are meant to total 20, but this card

does not so we know there is a mistake. Go through examples of how pupils

may have tried to fix the card by making one of the numbers smaller. Then

show the next slide, with a missing value.

? What would the missing value be? Explain how you know...

Take feedback from pupils and consider the strategies of finding the missing

number.

I know the total of the skills is equal to 20. The other two values total 12.

If my whole is 20 and one part is 12, then the other part is equal to 8.

I know the total is 20. If I subtract the other two values from 20 (counting

back on a number line), the number left will be the missing value.

Show pupils a superhero card with two missing values. (IWB 6) Pose the

question to the pupils:

? What could the missing values be?

? Is there more than one possible answer?

Take pupil feedback and role play the Let’s Explore task with another adult or

pupil.

Transition: number bonds within 20.


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Let’s Explore

Missing values: what are the possibilities?

Pupils to discuss and explore the different possibilities of the

missing numbers that could go into the empty boxes.

Encourage pupils to use mathematical thinking to help them to

systematically find what the missing numbers could be. If pupils guess

numbers, try to encourage them to consider what they learn when

numbers are incorrect.

This is an exploratory activity for pupils to consider a range of

options. At the teachers’ discretion using AfL, the activity can be

scaffolded further to only include one missing number.

Develop Learning

Creating Superhero cards

Explain that the MM Comics new range of superhero cards have not been very successful! They would like the pupils

to help them to design their own pack of superheroes. Show pupils the template of an empty superhero card. Remind

pupils of the criteria that needs to be met: the superhero needs 3 attributes and they must total 20. Ask pupils to give

suggestions about how they would complete a card. Use pupil feedback to start to complete a card.

? What numbers will you use for each skill? What rules must we remember?

Model using thinking aloud to complete a sample superhero card. Explicitly show a range of strategies to calculate the

four numbers. This can be through using physical representations (such as 20 cubes) or pictorial representations. This

will allow pupils to see that there is more than one approach to completing the problem.

Show another example with one number already completed: model making choices with high numbers which will total

over 25. After three numbers, encourage pupils to explain how they know there has been a mistake.

? What do you notice about the total of skills so far? Can you see a mistake?

Describe this to a partner and suggest how to fix the error. This can be followed up with further examples of modelling

by the teacher and TA in preparation for the Independent Task.



I know that the total of all the

numbers has to be 20. The number is

6. 20 – 6 = 14.

I need to find two numbers that add

up to 14. I know that 8 + 6 = 14.

I am going to check our answer by

adding all of the values. Six plus

six plus eight is equal to 20.






Adapting and Differentiating:

Constraints can be used to provide

more or less challenge in this activity.

Pupils can have the total increased to

50.

Pupils could only be allowed to use

specific numbers or, for example, odd/

even numbers.

Pupils can be given numbers and then

have to choose numbers from these to

test and use.

The task could be constrained to two

skills where pupils could find

possibilities, or increased to 6 or 8

skills.

Pupils could be given the constraint of

not being allowed to use numbers more

than once, or alternatively having to

use a number twice.

Ideas for Depth:

Give pupils completed

cards with errors. Can

pupils work out where

the mistake may have been.

Challenge pupils to see if they can use a pattern of numbers to complete the cards. For example,

can they use a set of consecutive numbers? Or numbers with a difference of 2?

Independent Task

Applying addition and subtraction to create superhero cards

Pupils are now challenged to create their own range of superhero cards. Give

them time to think about the different characters of superheroes they will

include.

This task may be suited to working in pairs or small groups, in order to give

pupils more opportunities to discuss their mathematical thinking and

decision making. A range of manipulatives from cubes to number lines can

support pupils in their learning.

Additionally, consider the range of constraints that may help to tailor pupils’

learning during the session (and, of course, teachers designing their own

adaptations). This might be through giving specific groups of pupils

manipulatives to use, or constraining the choices of numbers that pupils can

use.

Plenary

Missing value

Gudni has created his own character, Eggman. He is missing

one value.

? Can you calculate the missing value?

? How many ways can you find the answer?

Take feedback on the ways that pupils can solve this, linking to

the learning that has occurred during the Independent Task.



Copyright © Mathematics Mastery 2018

MM Comics Superheroes

Can you find what the missing values could be?

Have you found all of the possibilities?

Total: 20 Total: 20

Blobman Capeman

Skills Skills

Strength

Speed

Intelligence

Strength

Speed

Intelligence

6

9

do now new learning · the cards. for example, can they use a set of consecutive numbers? or...

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