Challenge Level

Try entering different sets of numbers in the number pyramids. How does the total at the top change?

Challenge Level

Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?

Challenge Level

Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?

Challenge Level

Create some shapes by combining two or more rectangles. What can you say about the areas and perimeters of the shapes you can make?

Challenge Level

My two digit number is special because adding the sum of its digits to the product of its digits gives me my original number. What could my number be?

Challenge Level

Surprising numerical patterns can be explained using algebra and diagrams...

Challenge Level

When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...

Challenge Level

Where should you start, if you want to finish back where you started?

Challenge Level

Play around with the Fibonacci sequence and discover some surprising results!

Challenge Level

Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...

Challenge Level

Think of two whole numbers under 10, and follow the steps. I can work out both your numbers very quickly. How?

A collection of short problems on creating algebraic expressions.

Challenge Level

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