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For younger learners

  • Early Years Foundation Stage

Secondary Games and Puzzles for Summer 2021

We have a challenge a day for you throughout the summer break...

Each weekday from 19 July to 31 August, a new game or puzzle will appear on this page.

After you've had a go at the day's challenge you may be able to compare your approach to the solutions we have published, which are based on students' work. 

You can also find Primary Games and Puzzles for Summer 2021.

Multiples Sudoku

Age 11 to 14
Challenge Level Yellow star

Each clue in this Sudoku is the product of the two numbers in adjacent cells.

Square It

Age 11 to 16
Challenge Level Yellow star

Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.

Connect Three

Age 11 to 16
Challenge Level Yellow starYellow star

In this game the winner is the first to complete a row of three. Are some squares easier to land on than others?

Got It

Age 7 to 14
Challenge Level Yellow starYellow star

A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.

Frogs

Age 11 to 14
Challenge Level Yellow star

How many moves does it take to swap over some red and blue frogs? Do you have a method?

Product Sudoku

Age 11 to 16
Challenge Level Yellow starYellow star

The clues for this Sudoku are the product of the numbers in adjacent squares.

Add to 200

Age 11 to 14
Challenge Level Yellow star

By selecting digits for an addition grid, what targets can you make?

Factors and Multiples Game

Age 7 to 16
Challenge Level Yellow star

A game in which players take it in turns to choose a number. Can you block your opponent?

Gabriel's Problem

Age 11 to 14
Challenge Level Yellow star

Gabriel multiplied together some numbers and then erased them. Can you figure out where each number was?

Cryptarithms

Age 11 to 14
Challenge Level Yellow star

Can you crack these cryptarithms?

The Remainders Game

Age 7 to 14
Challenge Level Yellow star

Play this game and see if you can figure out the computer's chosen number.

Diamond Collector

Age 11 to 16
Challenge Level Yellow star

Collect as many diamonds as you can by drawing three straight lines.

In the Bag

Age 11 to 14
Challenge Level Yellow star

Can you guess the colours of the 10 marbles in the bag? Can you develop an effective strategy for reaching 1000 points in the least number of rounds?

Countdown

Age 7 to 14
Challenge Level Yellow star

Here is a chance to play a version of the classic Countdown Game.

Magic Potting Sheds

Age 11 to 16
Challenge Level Yellow starYellow star

Mr McGregor has a magic potting shed. Overnight, the number of plants in it doubles. He'd like to put the same number of plants in each of three gardens, planting one garden each day. Can he do it?

Estimating Angles

Age 7 to 14
Challenge Level Yellow star

How good are you at estimating angles?

Treasure Hunt

Age 7 to 14
Challenge Level Yellow star

Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?

Nine Colours

Age 11 to 16
Challenge Level Yellow starYellow starYellow star

Can you use small coloured cubes to make a 3 by 3 by 3 cube so that each face of the bigger cube contains one of each colour?

Charlie's Delightful Machine

Age 11 to 16
Challenge Level Yellow star

Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?

Finding Factors

Age 14 to 16
Challenge Level Yellow star

Can you find the hidden factors which multiply together to produce each quadratic expression?

Fruity Totals

Age 7 to 16
Challenge Level Yellow star

In this interactivity each fruit has a hidden value. Can you deduce what each one is worth?

The Number Jumbler

Age 7 to 14
Challenge Level Yellow star

The Number Jumbler can always work out your chosen symbol. Can you work out how?

Alison's Quilt

Age 11 to 14
Challenge Level Yellow starYellow star

Nine squares are fitted together to form a rectangle. Can you find its dimensions?

Missing Multipliers

Age 7 to 14
Challenge Level Yellow star

What is the smallest number of answers you need to reveal in order to work out the missing headers?

Nice or Nasty

Age 7 to 14
Challenge Level Yellow star

There are nasty versions of this dice game but we'll start with the nice ones...

Difference Sudoku

Age 14 to 16
Challenge Level Yellow starYellow starYellow star

Use the differences to find the solution to this Sudoku.

ACE, TWO, THREE...

Age 11 to 14
Challenge Level Yellow star

Can you picture how to order the cards to reproduce Charlie's card trick for yourself?

LCM Sudoku

Age 14 to 16
Challenge Level Yellow starYellow star

Here is a Sudoku with a difference! Use information about lowest common multiples to help you solve it.

Amazing Card Trick

Age 11 to 14
Challenge Level Yellow starYellow star

How is it possible to predict the card?

Escape from the Castle

Age 7 to 14
Challenge Level Yellow starYellow star

Skippy and Anna are locked in a room in a large castle. The key to that room, and all the other rooms, is a number. The numbers are locked away in a problem. Can you help them to get out?

A First Product Sudoku

Age 7 to 14
Challenge Level Yellow star

Given the products of adjacent cells, can you complete this Sudoku?

Dicey Operations

Age 11 to 14
Challenge Level Yellow star

Who said that adding, subtracting, multiplying and dividing couldn't be fun?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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