Resources tagged with: Mental calculations
There are 52 NRICH Mathematical resources connected to Mental calculations, you may find related items under Calculations and numerical methods.
Broad Topics > Calculations and numerical methods > Mental calculations
5 by 5 Mathdokus
Can you use the clues to complete these 5 by 5 Mathematical Sudokus?
4 by 4 Mathdokus
Can you use the clues to complete these 4 by 4 Mathematical Sudokus?
Subtraction Slip
Can you spot the mistake in this video? How would you work out the answer to this calculation?
Compare the Calculations
Can you put these four calculations into order of difficulty? How did you decide?
Picture Your Method
Can you match these calculation methods to their visual representations?
Fruity Pairs
Which two items of fruit could Kate and Sam choose? Can you order the prices from lowest to highest?
Arranging Additions and Sorting Subtractions
Order these four calculations from easiest to hardest. How did you decide?
Can You Make 100?
How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?
Overlaps
Can you find ways to put numbers in the overlaps so the rings have equal totals?
Missing Multipliers
What is the smallest number of answers you need to reveal in order to work out the missing headers?
How Do You Do It?
This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.
Going Round in Circles
Mathematicians are always looking for efficient methods for solving problems. How efficient can you be?
Dicey Operations
Who said that adding, subtracting, multiplying and dividing couldn't be fun?
Countdown
Here is a chance to play a version of the classic Countdown Game.
Power Countdown
In this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.
Difference Sudoku
Use the differences to find the solution to this Sudoku.
Integrated Sums Sudoku
The puzzle can be solved with the help of small clue-numbers which are either placed on the border lines between selected pairs of neighbouring squares of the grid or placed after slash marks on the intersections between two diagonally adjacent squares.
Consecutive Seven
Can you arrange these numbers into 7 subsets, each of three numbers, so that when the numbers in each are added together, they make seven consecutive numbers?
Mind Reading
Think of a number, add one, double it, take away 3, add the number you first thought of, add 7, divide by 3 and take away the number you first thought of. You should now be left with 2. How do I know?
Multiplication Tables - Matching Cards
Practise your tables skills and try to beat your previous best score in this interactive game.
Shapes on the Playground
Sally and Ben were drawing shapes in chalk on the school playground. Can you work out what shapes each of them drew using the clues?
Where Can We Visit?
Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: x2 and -5. What do you think?
Days and Dates
Investigate how you can work out what day of the week your birthday will be on next year, and the year after...
Let's Get Flexible!
In this article for primary teachers, Ems outlines how we can encourage learners to be flexible in their approach to calculation, and why this is crucial.
Being Curious - Primary Number
Number problems for inquiring primary learners.
Dicey Operations in Line for Two
Dicey Operations for an adult and child. Can you get close to 1000 than your partner?
More Playing with Number Upper Primary
Related resources supporting pupils' understanding of multiplication and division through playing with numbers.
Current Playing with Number Upper Primary Teacher
Resources to support understanding of multiplication and division through playing with number.
More Playing with Number Lower Primary
Some additional activities to develop children's understanding of addition and subtraction of number through playing with number.
More Playing with Numbers Upper Primary
More resources to support understanding multiplication and division through playing with numbers
Mathdoku
Complete the Mathdoku grid using the clues. Can you convince us that the number you have chosen for each square has to be correct?
Clever Carl
What would you do if your teacher asked you add all the numbers from 1 to 100? Find out how Carl Gauss responded when he was asked to do just that.
Chocoholics
George and Jim want to buy a chocolate bar. George needs 2p more and Jim need 50p more to buy it. How much is the chocolate bar?
Transformations Tables
These grids are filled according to some rules - can you complete them?
Calculator Bingo
This is a game for two players. What must you subtract to remove the rolled digit from your number? The first to zero wins!
Wild Jack
A game for 2 or more players with a pack of cards. Practise your skills of addition, subtraction, multiplication and division to hit the target score.
Criss Cross Quiz
A game for 2 players. Practises subtraction or other maths operations knowledge.
Flip Flop - Matching Cards
Practise your number bonds whilst improving your memory in this matching pairs game.
Subtraction Squares
A game for 2 players. Using 2 dice, some counters and a games board, can you form a line of counters from one side of the board to the other?
Pass the Peas, Please
A game for 2 or more players. Practise your addition and subtraction with the aid of a game board and some dried peas!
Down to Nothing
A game for 2 or more people. Starting with 100, subratct a number from 1 to 9 from the total. You score for making an odd number, a number ending in 0 or a multiple of 6.
Fifteen
Can you spot the similarities between this game and other games you know? The aim is to choose 3 numbers that total 15.
Domino Magic Rectangle
An ordinary set of dominoes can be laid out as a 7 by 4 magic rectangle in which all the spots in all the columns add to 24, while those in the rows add to 42. Try it! Now try the magic square...
Is it Magic or Is it Maths?
Here are three 'tricks' to amaze your friends. But the really clever trick is explaining to them why these 'tricks' are maths not magic. Like all good magicians, you should practice by trying them. Can you explain how they work?
Prime Magic
Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?