Original notes<br />
    <br />
    I have used this problem with heterogeneous classes of children
    aged 10 to 13 and found them all to be very engaged and
    innovative in reaching solutions. <br />
    <br />
    As ever, to have ready a selection of the raw materials
    necessary to allow and encourage hands on exploration to
    discover and prove solutions is a must. <br />
    <br />
    This problem applies and extends skills and knowledge in
    several directions; estimation, measuring both linear and mass,
    construction, surface area, proportion, methods of calculating
    the volume of different shapes.... Part of the benefit of such
    a question is that it sends a loud message about how we use
    mathematical vocabulary and how precisely it describes
    concepts. What does it means to double something? If we are
    referring to a three dimensional object, which surfaces do we
    have to double? What are the implications for the increase in
    size? <br />
    <br />
    Additionally, having small groups present to the class their
    'findings', allows them to practice using their mathematical
    vocabulary in a refined way. <br />
    <br />
    Children have taken the investigation further. For example: one
    group wanted to find out what percentage of corn kernels didn't
    pop. Another group wanted to know if there was difference
    between the volume of popped corn for different brands of
    corn.<br />