Year 8 Conjecturing and generalising

  • Subtraction Surprise
    problem
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    Subtraction Surprise

    Age
    7 to 14
    Challenge level
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    Try out these calculations. Are you surprised by the results?

  • Method in multiplying madness?
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    Method in Multiplying Madness?

    Age
    7 to 14
    Challenge level
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    Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?

  • spaces for exploration
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    Spaces for Exploration

    Alf Coles writes about how he tries to create 'spaces for exploration' for the students in his classrooms.

  • A green frog.
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    Frogs

    Age
    11 to 14
    Challenge level
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    How many moves does it take to swap over some red and blue frogs? Do you have a method?

  • Flippin' discs
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    Flippin' Discs

    Age
    11 to 14
    Challenge level
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    Discs are flipped in the air. You win if all the faces show the same colour. What is the probability of winning?

  • Interactive Spinners
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    Interactive Spinners

    Age
    11 to 14
    Challenge level
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    This interactivity invites you to make conjectures and explore probabilities of outcomes related to two independent events.

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    Reaction Timer

    Age
    11 to 14
    Challenge level
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    This problem offers you two ways to test reactions - use them to investigate your ideas about speeds of reaction.

  • Crossed Ends
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    Crossed Ends

    Age
    11 to 14
    Challenge level
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    Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?

  • Two white rectangles on a wooden background, arranged like an equals sign.
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    Can They Be Equal?

    Age
    11 to 14
    Challenge level
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    Can you find rectangles where the value of the area is the same as the value of the perimeter?

  • Keep it simple
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    Keep It Simple

    Age
    11 to 14
    Challenge level
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    Can all unit fractions be written as the sum of two unit fractions?

  • How much can we spend?
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    How Much Can We Spend?

    Age
    11 to 14
    Challenge level
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    A country has decided to have just two different coins. Which totals can be made? Is there a largest total that cannot be made? How do you know?

  • Your number was...
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    Your Number Was...

    Age
    11 to 14
    Challenge level
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    Think of a number and follow my instructions. Tell me your answer, and I'll tell you what you started with! Can you explain how I know?

  • What numbers can we make?
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    What Numbers Can We Make?

    Age
    11 to 14
    Challenge level
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    Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?

  • Constructing Triangles
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    Constructing Triangles

    Age
    11 to 14
    Challenge level
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    Generate three random numbers to determine the side lengths of a triangle. What triangles can you draw?

  • Forwards Add Backwards
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    Forwards Add Backwards

    Age
    11 to 14
    Challenge level
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    What happens when you add a three digit number to its reverse?

  • Polygon Rings
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    Polygon Rings

    Age
    11 to 14
    Challenge level
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    Join pentagons together edge to edge. Will they form a ring?

  • Isometric Areas
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    Isometric Areas

    Age
    11 to 14
    Challenge level
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    We usually use squares to measure area, but what if we use triangles instead?

  • Where can we visit?
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    Where Can We Visit?

    Age
    11 to 14
    Challenge level
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    Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: ×2 and -5. What do you think?

  • Egyptian Fractions
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    Egyptian Fractions

    Age
    11 to 14
    Challenge level
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    The Egyptians expressed all fractions as the sum of different unit fractions. Here is a chance to explore how they could have written different fractions.

  • Farey Sequences
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    Farey Sequences

    Age
    11 to 14
    Challenge level
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    There are lots of ideas to explore in these sequences of ordered fractions.

  • Coordinate Patterns
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    Coordinate Patterns

    Age
    11 to 14
    Challenge level
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    Charlie and Alison have been drawing patterns on coordinate grids. Can you picture where the patterns lead?

  • Stars
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    Stars

    Age
    11 to 14
    Challenge level
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    Can you work out what step size to take to ensure you visit all the dots on the circle?

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    Right Angles

    Age
    11 to 14
    Challenge level
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    Can you make a right-angled triangle on this peg-board by joining up three points round the edge?

  • Route to infinity
    problem
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    Route to Infinity

    Age
    11 to 14
    Challenge level
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    Can you describe this route to infinity? Where will the arrows take you next?

  • Power mad!
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    Power Mad!

    Age
    11 to 14
    Challenge level
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    Powers of numbers behave in surprising ways. Take a look at some of these and try to explain why they are true.

  • Changing areas, changing volumes
    problem
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    Changing Areas, Changing Volumes

    Age
    11 to 14
    Challenge level
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    How can you change the surface area of a cuboid but keep its volume the same? How can you change the volume but keep the surface area the same?

  • Non-Transitive Dice
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    Non-Transitive Dice

    Age
    11 to 14
    Challenge level
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    Alison and Charlie are playing a game. Charlie wants to go first so Alison lets him. Was that such a good idea?

  • Seven Squares
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    Seven Squares

    Age
    11 to 14
    Challenge level
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    Watch these videos to see how Phoebe, Alice and Luke chose to draw 7 squares. How would they draw 100?

  • Hourglass with blue sand.
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    Estimating Time

    Age
    11 to 14
    Challenge level
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    How well can you estimate 10 seconds? Investigate with our timing tool.

  • Same Answer
    problem
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    Same Answer

    Age
    11 to 14
    Challenge level
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    Aisha's division and subtraction calculations both gave the same answer! Can you find some more examples?