Why we like this activity....
Every country in the world, rich enough to give its citizens free education, thinks it important that their entire
population knows how to calculate the volume of different types of prism . Your challenge is to see if you can
apply this knowledge to create NETS of 3D shapes , that fold up perfectly! together to make a volume that reveals
something hopefully both surprising and interesting about the world you live in. It's often a relief, liberation, and/or
eye opener to put your life into the wider context of the 7 billion person world we live in!

There's something for everyone: are you good at building things, but find the calculations a little harder? Try the
Excel formula tables that do the calculations for you. Are you good at calculating but find precise measuring and
putting things together precisely challenging? Find a partner whose good at building and you make the perfect team!

How this activity can be used....
All data sources that provided the statisitics used here can be found at the thinkmathematics wikispace. There is also
a video section for MP3 & MP4 downloads (ipod, smartphones: Samsung, Nokia, Blackberry, HTC, LG etc.). We are
trying to pool in one place as big a maths podcast/movie library as possible so please don't hesitate to email us any
good links you have that we can share on the Wiki.

A nice introduction may be to visit www.gapminder.org to get a feel for the power of statistics to inform us about the
world around us. Which Prisms do you think you can make the net of? Can you calculate the lengths correctly given
the volume needed? Use the shape on the sheet e.g. cuboid, triangular prism etc. to see which prism you're going to
have to build. If you fancy a challenge, why not do a Plan, Front and Side View of an unusual form of prism (don't
forget the measurements) and ask your teacher if you can have a go at making that!

Here are a few websites you may find useful to remind you how to find the volume of a prism:

http://www.teachers.ash.org.au/jeather/maths/dictionary.html

http://www.learner.org/interactives/geometry/3d_prisms.html

This activity leads on and forms part of the same exhibition as the "The Rice Show: Estimation" activity.

What to expect when using this activity, from our experience...
•  Measurements need to fit the size of the card available ! There are many different Triangular prisms that
all have the same volume. Your challenge is to find a set of measurements that fit your card and at the same time,
give you the volume required! (the Teacher may choose to calculate the measurements for you beforehand or give
you an Excel sheet that calculates the necessary lengths).

•  Construction & Measurement takes longer than you think !

•  Be careful! No point rushing only to find 1hour of work maybe wasted because you're measurements are wrong
or the sides don't meet up properly: “Measure twice, cut once!”

•  Lots of team work , which often means dividing up whose going to construct which faces of the Net so that
you're not standing around bored with nothing to do. Get involved, will your prism win the jury prize as voted for by
the rest of the class? And if it doesn't, because we can't all win all the time!, don't let it be because of a lack of
effort/trying.

Extra notes

Author/Date: Oliver Bowles 30.12.09

Credits: Jim Noble for driving forward the idea with typical enthusiasm, patience and creativity.