Challenge Level

"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?

Challenge Level

Investigate and explain the patterns that you see from recording just the units digits of numbers in the times tables.

Challenge Level

Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?

Challenge Level

Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. How many different ways can you do this?

Challenge Level

One block is needed to make an up-and-down staircase, with one step up and one step down. How many blocks would be needed to build an up-and-down staircase with 5 steps up and 5 steps down?

Challenge Level

Each light in this interactivity turns on according to a rule. What happens when you enter different numbers? Can you find the smallest number that lights up all four lights?

Challenge Level

Can you continue this pattern of triangles and begin to predict how many sticks are used for each new "layer"?