If it takes four men one day to build a wall, how long does it take 60,000 men to build a similar wall?

Use your knowledge of angles to work out how many degrees the hour and minute hands of a clock travel through in different amounts of time.

Great Granddad is very proud of his telegram from the Queen congratulating him on his hundredth birthday and he has friends who are even older than he is... When was he born?

A paradox is a statement that seems to be both untrue and true at the same time. This article looks at a few examples and challenges you to investigate them for yourself.

Use the clocks to investigate French decimal time in this problem. Can you see how this time system worked?

How many times in twelve hours do the hands of a clock form a right angle? Use the interactivity to check your answers.

Which segment on a digital clock is lit most each day? Which segment is lit least? Does it make any difference if it is set to 12 hours or 24 hours?

Do you know the rhyme about ten green bottles hanging on a wall? If the first bottle fell at ten past five and the others fell down at 5 minute intervals, what time would the last bottle fall down?

Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?

Use the interactivity to move Mr Pearson and his dog. Can you move him so that the graph shows a curve?

These clocks have only one hand, but can you work out what time they are showing from the information?

Can you create a story that would describe the movement of the man shown on these graphs? Use the interactivity to try out our ideas.

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.

Alice's mum needs to go to each child's house just once and then back home again. How many different routes are there? Use the information to find out how long each road is on the route she took.

Not everybody agreed that the Third Millennium actually began on January 1st 2000. Find out why by reading this brief article.

This article explains how Greenwich Mean Time was established and in fact, why Greenwich in London was chosen as the standard.

Two engines, at opposite ends of a single track railway line, set off towards one another just as a fly, sitting on the front of one of the engines, sets off flying along the railway line...

Can you order pictures of the development of a frog from frogspawn and of a bean seed growing into a plant?

Can you put these mixed-up times in order? You could arrange them in a circle.

If Tom wants to learn to cook his favourite supper, he needs to make a schedule so that everything is ready at the same time.

The pages of my calendar have got mixed up. Can you sort them out?

In this matching game, you have to decide how long different events take.

What can you say about when these pictures were taken?

Galileo, a famous inventor who lived about 400 years ago, came up with an idea similar to this for making a time measuring instrument. Can you turn your pendulum into an accurate minute timer?

A game for two or more players that uses a knowledge of measuring tools. Spin the spinner and identify which jobs can be done with the measuring tool shown.

Every day at noon a boat leaves Le Havre for New York while another boat leaves New York for Le Havre. The ocean crossing takes seven days. How many boats will each boat cross during their journey?

A bus route has a total duration of 40 minutes. Every 10 minutes, two buses set out, one from each end. How many buses will one bus meet on its way from one end to the other end?

I found these clocks in the Arts Centre at the University of Warwick intriguing - do they really need four clocks and what times would be ambiguous with only two or three of them?

Noticing the regular movement of the Sun and the stars has led to a desire to measure time. This article for teachers and learners looks at the history of man's need to measure things.

A train leaves on time. After it has gone 8 miles (at 33mph) the driver looks at his watch and sees that the hour hand is exactly over the minute hand. When did the train leave the station?

This article for teachers suggests ways in which dinosaurs can be a great context for discussing measurement.

What is the date in February 2002 where the 8 digits are palindromic if the date is written in the British way?

This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.

Sometime during every hour the minute hand lies directly above the hour hand. At what time between 4 and 5 o'clock does this happen?

My cousin was 24 years old on Friday April 5th in 1974. On what day of the week was she born?

At the time of writing the hour and minute hands of my clock are at right angles. How long will it be before they are at right angles again?

This month there is a Friday the thirteenth and this year there are three. Can you explain why every year must contain at least one Friday the thirteenth?

On a digital 24 hour clock, at certain times, all the digits are consecutive. How many times like this are there between midnight and 7 a.m.?

During the third hour after midnight the hands on a clock point in the same direction (so one hand is over the top of the other). At what time, to the nearest second, does this happen?

In this version of the story of the hare and the tortoise, the race is 10 kilometres long. Can you work out how long the hare sleeps for using the information given?

Calendars were one of the earliest calculating devices developed by civilizations. Find out about the Mayan calendar in this article.

Anne completes a circuit around a circular track in 40 seconds. Brenda runs in the opposite direction and meets Anne every 15 seconds. How long does it take Brenda to run around the track?

On a digital clock showing 24 hour time, over a whole day, how many times does a 5 appear? Is it the same number for a 12 hour clock over a whole day?

Follow the journey taken by this bird and let us know for how long and in what direction it must fly to return to its starting point.

Read this article to find out the mathematical method for working out what day of the week each particular date fell on back as far as 1700.

How far have these students walked by the time the teacher's car reaches them after their bus broke down?

Nirmala and Riki live 9 kilometres away from the nearest market. They both want to arrive at the market at exactly noon. What time should each of them start riding their bikes?

Stuart's watch loses two minutes every hour. Adam's watch gains one minute every hour. Use the information to work out what time (the real time) they arrived at the airport.