Exploring and noticing

  • Perimeter Expressions
    problem
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    Perimeter Expressions

    Age
    11 to 14
    Challenge level
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    Create some shapes by combining two or more rectangles. What can you say about the areas and perimeters of the shapes you can make?

  • 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?

  • Can you Make 100?
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    Can You Make 100?

    Age
    11 to 14
    Challenge level
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    How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?

  • Fractions Rectangle
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    Fractions Rectangle

    Age
    11 to 14
    Challenge level
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    The large rectangle is divided into quadrilaterals and triangles. Can you untangle what fractional part is represented by each of the ten numbered shapes?

  • Number Families
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    Number Families

    Age
    11 to 14
    Challenge level
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    How many different number families can you find?

  • Odds, Evens and More Evens
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    Odds, Evens and More Evens

    Age
    11 to 14
    Challenge level
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    Alison, Bernard and Charlie have been exploring sequences of odd and even numbers, which raise some intriguing questions...

  • Sieve of Eratosthenes
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    Sieve of Eratosthenes

    Age
    11 to 14
    Challenge level
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    Follow this recipe for sieving numbers and see what interesting patterns emerge.

  • 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?

  • Olympic Records
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    Olympic Records

    Age
    11 to 14
    Challenge level
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    Can you deduce which Olympic athletics events are represented by the graphs?

  • Summing Consecutive Numbers
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    Summing Consecutive Numbers

    Age
    11 to 14
    Challenge level
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    15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?