Pumpkin Patch
Seega
Alquerque
Introducing NRICH TWILGO
Air Nets
Like a Circle in a Spiral
Fruity Totals
In this interactivity each fruit has a hidden value. Can you deduce what each one is worth?
Clocking off
Prime Magic
Sprouts
What's it worth?
There are lots of different methods to find out what the shapes are worth - how many can you find?
Shaping the universe III - to infinity and beyond
Nine Colours
LOGO Challenge - Circles as animals
Instant Insanity
Given the nets of 4 cubes with the faces coloured in 4 colours, build a tower so that on each vertical wall no colour is repeated, that is all 4 colours appear.
Searching for mean(ing)
LOGO Challenge - Triangles-Squares-Stars
Hamiltonian Cube
Find the length along the shortest path passing through certain points on the cube.
Cuboid Challenge
What's the largest volume of box you can make from a square of paper?
Take Three From Five
Caroline and James pick sets of five numbers. Charlie tries to find three that add together to make a multiple of three. Can they stop him?
Triangles in the middle
What is the question?
Pythagoras Proofs
Can you make sense of these three proofs of Pythagoras' Theorem?
Parallelogram It
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a parallelogram.
Charlie's delightful machine
Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?
Charting success
Rhombus It
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a rhombus.
Sliding Puzzle
Charting more success
Ding Dong Bell
Marbles in a box
The Bridges of Konigsberg
Shaping the universe I - planet Earth
Semi-regular Tessellations
Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?
Funny Factorisation
Yih or Luk tsut k'i or Three Men's Morris
Shaping the universe II - the solar system
Around and Back
Packing 3D shapes
Tennis Training
Painted Purple
Out of the Window
Which is bigger?
Cubic Covering
Eulerian
Which of the five diagrams below could be drawn without taking the pen off the page and without drawing along a line already drawn?
Partly Painted Cube
Pyramidal n-gon
Jam
To avoid losing think of another very well known game where the patterns of play are similar.
Just rolling round
Bus Stop
Dating made Easier
In or Out?
Four arcs are drawn in a circle to create a shaded area. What fraction of the area of the circle is shaded?
Gnomon dimensions
A question of scale
Wari
Terminology
Coke machine
Inside Out
There are 27 small cubes in a 3 x 3 x 3 cube, 54 faces being visible at any one time. Is it possible to reorganise these cubes so that by dipping the large cube into a pot of paint three times you can colour every face of all of the smaller cubes?
Vector journeys
Doesn't add up
In this problem we are faced with an apparently easy area problem, but it has gone horribly wrong! What happened?
Trisected Triangle
Four tiles are given. For which of them can three be placed together to form an equilateral triangle?
Just Opposite
Sliced
Factorising with Multilink
Fermat's Poser
Rectangle Rearrangement
Quadratic Patterns
Surprising numerical patterns can be explained using algebra and diagrams...
Iff
At right angles
Back fitter
10 graphs of experimental data are given. Can you use a spreadsheet to find algebraic graphs which match them closely, and thus discover the formulae most likely to govern the underlying processes?
Pick's Theorem
Circuit training
What's that graph?
Can you work out which processes are represented by the graphs?
A Problem of time
Pythagoras Perimeters
Tetra Square
Building Gnomons
Surprising Transformations
I took the graph y=4x+7 and performed four transformations. Can you find the order in which I could have carried out the transformations?