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Chesswood Junior School

Chesswood Junior School

Mental Maths Knowledge & Skills

This page contains a number of tips, strategies and games to support children with learning key maths facts.  Quite often children are able to calculate some of these facts, but require a bit of time to recall them - these games help children to be able to really know them and recall them instantly - as if they were telling someone their name or their favourite pet or food!

Speed of recall and accuracy of recall helps children when attempting much trickier problems in Maths - for example written addition and subtraction of 2, 3 and 4-digit numbers - many of the calculations used here is based on being able to recall and use number bonds.

Please note this page is currently under development with new resources being added.

Helpful APPS
App Link How does it help?
White Rose 1-minute Maths


Apple App Store
Google Play
Amazon Kindle



These activities help children to quickly recognise quantities up to 10 .

Addition + Subtraction

These activities help children to quickly recall addition within 100.  There various different tasks including number bonds to 10, 20 and 100.  These help children to calculate quickly mentally and support children's confidence with written methods.



Apple App Store
Google Play
Amazon Kindle

Please note - all children are supplied with a log in for Numbots - it is the same as their log in for TT Rock Stars.  Many of the skills that are unlocked on Challenge Mode can also be practised using the White Rose 1-minute Maths app.

Story Mode

In Story Mode, the emphasis is on mathematical concepts and is underpinned by a mastery approach to teaching. Story Mode features visual representations, procedural variation, exposure to different calculation strategies and interleaved material all in very carefully sequenced order.

Challenge Mode

In Challenge Mode, the emphasis is on rapid responses to essential facts and simple sums, against the clock.

Challenge Mode is locked for new users and is unlocked once players reach a certain level on Story Mode. It’s currently set to unlock part way through Tin stage. There are 20 Challenge levels and only the first is unlocked to begin with. To unlock the next Challenge, players must correctly answer 12 questions in a minute.

Website + Link How does it help?
Activity + Description How does it help?
Strategy + Description Example

Compensation – when you add or subtract too much and then adjust, e.g. to add numbers like 19/29/39, etc you might add 20/30/40 and then subtract 1.


Bridging to a multiple of 10 – when you split the second addend so that count up to the nearest multiple of 10 and then count on the remainder, e.g. to add 27 and 5 you might add 3 then add 2. The same principle applies in reverse when subtracting, e.g. for 23 – 5.


Partitioning – when you split (partition) the 10s and 1s and add/subtract them separately before recombining, e.g. to add 27 and 32 you might add 20 and 30, 7 and 2 and then combine the totals.