The Enigma Project's James Grime has created a video code challenge. Watch it here!

In this problem, we define complex numbers and invite you to explore what happens when you add and multiply them.

Video showing how to use the Number Plumber

Can you find out what is special about the dimensions of rectangles you can make with squares, sticks and units?

Time for a little mathemagic! Choose any five cards from a pack and show four of them to your partner. How can they work out the fifth?

Watch the video to see how Charlie works out the sum. Can you adapt his method?

Watch the video to see how to add together an arithmetic sequence of numbers efficiently.

As part of Liverpool08 European Capital of Culture there were a huge number of events and displays. One of the art installations was called "Turning the Place Over". Can you find our how it works?

Watch the video to see how to sum the sequence. Can you adapt the method to sum other sequences?

Alison has created two mappings. Can you figure out what they do? What questions do they prompt you to ask?

Alf and Tracy explain how the Kingsfield School maths department use common tasks to encourage all students to think mathematically about key areas in the curriculum.

Whirl a conker around in a horizontal circle on a piece of string. What is the smallest angular speed with which it can whirl?

These models have appeared around the Centre for Mathematical Sciences. Perhaps you would like to try to make some similar models of your own.

The tangles created by the twists and turns of the Conway rope trick are surprisingly symmetrical. Here's why!

Which of these triangular jigsaws are impossible to finish?

In this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.

Design and test a paper helicopter. What is the best design?

Is there a relationship between the coordinates of the endpoints of a line and the number of grid squares it crosses?

Caroline and James pick sets of five numbers. Charlie chooses three of them that add together to make a multiple of three. Can they stop him?

A picture is made by joining five small quadrilaterals together to make a large quadrilateral. Is it possible to draw a similar picture if all the small quadrilaterals are cyclic?

Can you visualise whether these nets fold up into 3D shapes? Watch the videos each time to see if you were correct.

Steve has created two mappings. Can you figure out what they do? What questions do they prompt you to ask?