Exploring and noticing

There are 412 NRICH Mathematical resources connected to Exploring and noticing
Sliding Game
game

Sliding game

A shunting puzzle for 1 person. Swop the positions of the counters at the top and bottom of the board.
My New Patio
problem

My new patio

Age
7 to 11
Challenge level
filled star filled star empty star
What is the smallest number of tiles needed to tile this patio? Can you investigate patios of different sizes?
One Million to Seven
problem

One million to seven

Age
7 to 11
Challenge level
filled star filled star filled star
Start by putting one million (1 000 000) into the display of your calculator. Can you reduce this to 7 using just the 7 key and add, subtract, multiply, divide and equals as many times as you like?
There's always One isn't there
problem

There's always one isn't there

Age
14 to 16
Challenge level
filled star filled star filled star
Take any pair of numbers, say 9 and 14. Take the larger number, fourteen, and count up in 14s. Then divide each of those values by the 9, and look at the remainders.
Last Biscuit
game

Last biscuit

Can you find a strategy that ensures you get to take the last biscuit in this game?

Alphabet Soup
problem

Alphabet soup

Age
11 to 14
Challenge level
filled star empty star empty star
This challenge is to make up YOUR OWN alphanumeric. Each letter represents a digit and where the same letter appears more than once it must represent the same digit each time.
Special 24
problem

Special 24

Age
7 to 11
Challenge level
filled star filled star empty star
Find another number that is one short of a square number and when you double it and add 1, the result is also a square number.
1, 2, 3, 4, 5
problem

1, 2, 3, 4, 5

Age
7 to 11
Challenge level
filled star filled star empty star
Using the numbers 1, 2, 3, 4 and 5 once and only once, and the operations x and ÷ once and only once, what is the smallest whole number you can make?
Tricky Triangles
problem

Tricky triangles

Age
5 to 7
Challenge level
filled star filled star filled star
Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Lawn Border
problem

Lawn border

Age
5 to 11
Challenge level
filled star empty star empty star
If I use 12 green tiles to represent my lawn, how many different ways could I arrange them? How many border tiles would I need each time?