Learn why building number sense is so important in preschool and how using an estimation jar will help.
Many of my students can count above 20. Several more can count to 100. A couple of children can count past 100 but can they actually count out 100 objects accurately?
Introducing an estimation jar can be a fun way to begin looking at bigger numbers and modelling strategies for counting different amounts correctly.
Introducing an estimation jar can be a fun way to begin looking at bigger numbers and modelling strategies for counting different amounts correctly.
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WHY IS NUMBER SENSE IMPORTANT?
You often hear people use the term number sense when they’re talking about math. But what does it mean?
Number sense is a group of skills that allow children to work with confidently with numbers.
It includes basic math skills like understanding more/less, larger/smaller; being able to subitise small amounts (see the amount rather than have to count the objects); realising that symbols (numbers) represent quantities (3 means three cookies on the plate); being able to compare numbers and understand their value (8 is more than 4); that numbers have an order or pattern to them and the relationships between
In the Early Years, children need repeated opportunities to experience number to help them build an understanding and fluency of basic math concepts. They need to learn to identify numbers, understand quantity and learn how to count
In the Early Years, children need repeated opportunities to experience number to help them build an understanding and fluency of basic math concepts. They need to learn to identify numbers, understand quantity and learn how to count
For children struggling with number sense, it can lead to challenges in school and in everyday life.
Working with manipulatives like blocks are key to understand the relationships between amounts.
Create invitations to count that involve matching number symbols to quantities.
Use different representations of number so children can learn that numerals are the same as number words.
Getting lots of practice estimating and counting objects.
Teach children how to count by organising their objects so there is a clear start and stopping point. Line them up if there's only a handful or teach them to group to 10 to make counting larger amounts more accurate.
For me, one of the easiest ways to teach magnitude (how many/how much) is by using an estimation station in class. Using an estimation jar also allows you to model how to count.
It works quite simply.
Each morning the children estimate how many objects are in the jar as part of their morning routine and together we count them during our Maths lesson to see who's guess is the closest. They write their guess along with their name on a small piece of blank paper I have ready near the estimation jar.
I try to change the objects everyday and the children have certainly been excited to find out what is in the jar each day.
I place different sized objects in the jar and different amounts so they learn that 'full' doesn't necessarily equal 'most'. Sometimes I'll only half fill the jar with smaller objects like coins or counters so they can clearly see their guess needs to take into consideration what is in the jar not how full it is.
When you first start, I would only use smaller amounts (less than 50) then work your way up to amounts greater than 100 to then allow you to model the different counting strategies.
'They are big objects in the jar today, we could count by 1s.'
Or 'There are lots of small objects, we could count by 5s or 10s, our friendly number if we put them in groups first.'
We also order our guesses.
As you can see from the photos, the children have placed them along the floor to compare to the amount of objects counted. Having them write their guesses is a great way to them to learn that those symbols '34' represent an amount so writing '1236728' won't be close to correct.
It's the perfect tool for modelling whatever math skill you are teaching - cardinality, counting by 1s, grouping, skip counting, place value.
We've also been using a number of different tools to help us count correctly.
I'm frequently drawing number lines on the carpet in class with chalk. We discuss how we should number it before we start to count. It also helps bring their own guess into focus when compared to the whole class so if they are the one person still writing '1236728' a week in when the jar is still only half full of toy cars, some additional intervention might be necessary.
I also bought a starter set of Numicon earlier in the year and they have quickly become my favourite math tool for working with number.
Our Numicon set has been used for looking at number bonds, making simple patterns, building number lines and introducing odd and even numbers.
We've labelled clocks with them, matched them with numerals and made symmetrical pictures with them. I love the visual support they provide young learners and have already added to our first set.
Continue to provide lots of opportunities for your class to guess how many.
HOW TO TEACH NUMBER SENSE
Children can be taught these key concepts with time and practice. Number-sense skills do need to be intentionally taught in the same way we teach spelling, reading and writing skills.
Generally, a child struggling who has weak number sense, will benefit from more hands-on play based learning than completing more worksheets.
Children can be taught these key concepts with time and practice. Number-sense skills do need to be intentionally taught in the same way we teach spelling, reading and writing skills.
Generally, a child struggling who has weak number sense, will benefit from more hands-on play based learning than completing more worksheets.
Working with manipulatives like blocks are key to understand the relationships between amounts.
Create invitations to count that involve matching number symbols to quantities.
Use different representations of number so children can learn that numerals are the same as number words.
Getting lots of practice estimating and counting objects.
Teach children how to count by organising their objects so there is a clear start and stopping point. Line them up if there's only a handful or teach them to group to 10 to make counting larger amounts more accurate.
Count lots of different materials. Start introducing some reasoning to how to count - a handful of objects can be counted in a single line but if I want to count a container full, I might use a different strategy.
Learn strategies for checking an answer for accuracy. Counting a container of objects by tipping them out and counting them one by one as you drop them back in the container doesn't make it easy to double check your total whereas placing them in groups will.
Use other tools like ten frames, 2 x ten frames, 0-120 charts to make organising your objects easier to count.
CREATING AN ESTIMATION STATION IN CLASS
For me, one of the easiest ways to teach magnitude (how many/how much) is by using an estimation station in class. Using an estimation jar also allows you to model how to count.
It works quite simply.
Each morning the children estimate how many objects are in the jar as part of their morning routine and together we count them during our Maths lesson to see who's guess is the closest. They write their guess along with their name on a small piece of blank paper I have ready near the estimation jar.
I try to change the objects everyday and the children have certainly been excited to find out what is in the jar each day.
I place different sized objects in the jar and different amounts so they learn that 'full' doesn't necessarily equal 'most'. Sometimes I'll only half fill the jar with smaller objects like coins or counters so they can clearly see their guess needs to take into consideration what is in the jar not how full it is.
When you first start, I would only use smaller amounts (less than 50) then work your way up to amounts greater than 100 to then allow you to model the different counting strategies.
Before we start counting, we always discuss how best to count the objects.
'They are big objects in the jar today, we could count by 1s.'
Or 'There are lots of small objects, we could count by 5s or 10s, our friendly number if we put them in groups first.'
We also order our guesses.
As you can see from the photos, the children have placed them along the floor to compare to the amount of objects counted. Having them write their guesses is a great way to them to learn that those symbols '34' represent an amount so writing '1236728' won't be close to correct.
It's the perfect tool for modelling whatever math skill you are teaching - cardinality, counting by 1s, grouping, skip counting, place value.
We've also been using a number of different tools to help us count correctly.
I'm frequently drawing number lines on the carpet in class with chalk. We discuss how we should number it before we start to count. It also helps bring their own guess into focus when compared to the whole class so if they are the one person still writing '1236728' a week in when the jar is still only half full of toy cars, some additional intervention might be necessary.
I also bought a starter set of Numicon earlier in the year and they have quickly become my favourite math tool for working with number.
You can see how we've used them to support the concept of 10 being a friendly number to count by.
Our Numicon set has been used for looking at number bonds, making simple patterns, building number lines and introducing odd and even numbers.
We've labelled clocks with them, matched them with numerals and made symmetrical pictures with them. I love the visual support they provide young learners and have already added to our first set.
Just make sure the children know that estimates are just guesses. They might not guess the actual amount but you want to see their estimation skills improve as you use the estimation jar. With practice, I find all of my students' guesses become closer to the actual number of objects.
Grab our FREE estimation jar labels for your classroom!
