How many six digit numbers are there which DO NOT contain a 5?

Can you find different ways of showing the same number? Try this matching game and see!

Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?

Dotty Six is a simple dice game that you can adapt in many ways.

A task which depends on members of the group noticing the needs of others and responding.

These interactive dominoes can be dragged around the screen.

While musing about the difficulties children face in comprehending number structure, notation, etc., it occured to the author that there is a vast array of occasions when numbers and signs are used. . . .

What could these drawings, found in a cave in Spain, represent?

This article explains how credit card numbers are defined and the check digit serves to verify their accuracy.

There are six numbers written in five different scripts. Can you sort out which is which?

Consider all two digit numbers (10, 11, . . . ,99). In writing down all these numbers, which digits occur least often, and which occur most often ? What about three digit numbers, four digit numbers. . . .

How many positive integers less than or equal to 4000 can be written down without using the digits 7, 8 or 9?