Weights

The activities outlined below explore ideas around weight and size (although not all small things are light or large things heavy). While they are listed in a sequence you can do them in any order.

=**Some things are light**=

Most of us have hair on our heads, some more than others. How much weight is sitting on the top of your head? Every day! How might you work it out? Describe the process before you start and then make notes / take photographs as you work through it. What were your findings? What did you learn about measuring the weight of light things?
 * Getting ahead**

We have just been through the season of autumn and been surrounded by yellow and red leaves. While they seem light and delicate as they float singly to the ground I wonder just how much all of the leaves on a tree, in our schools / town / district, country weigh. Pick a tree somewhere around your classroom and estimate the weight of leaves on it. How many leaves do you think there are? Write down your estimates - compare them. How much do you think they might weigh? How might you weigh all of the leaves on the tree? Describe your method then go out and try it. If it does require the removal of some leaves (in the interests of mathematics) you had better check with someone first. Now you have a feel for the weight of leaves on one tree try and estimate the weight of leaves in the schools grounds or the park or the town. Now if we take all of those to the 'dump' what are the implications. Is it the same for grass (how much does one blade of grass weigh?) - talk to the caretaker maybe.
 * Autumn leaves**

There are more water molecules in a glass of water than there are glasses of water in the sea. Talk about this statement with others in your class and at home - what does it tell you about the size of molecules - and then we find out that a water molecule is made up of three atoms and that atoms are made up of even smaller pieces. Some things are really tiny! Talk about light things. Why is a dandelion so light? How about a strand of your hair - a strand of hair is about 500000 atoms thick (nobody has actually counted them and some believe each strand may be up to one million atoms in width) which means there are billions and billions of atoms in each strand of hair on your head! Each one weighs something.
 * My small explorations**

What are some really light things in our natural world - especially from New Zealand. Write an article that you can share with others. Include at least one illustration. You might look at one of our [|NZ bats].
 * Your challenge**

Other 'light' things - most are also small The [|bumblebee bat.] [|Birds]? [|Frogs] - they don't give a weight but you might get an idea from its size! [|Insects] - now this is tiny.

=And some things are not so light=

How much does the water in your school pool weigh? How might you work it out (put the pool on the bathroom scales??)? Estimate how much you think it will weigh and then describe your way of working it out. Now go and try it and make a not of your working out. How much does the water in your pool weigh? How good was your estimate? [if your school does not have a pool you can use these measurements 6m wide by 15m long by 1m deep] The principal's car weighs approximately 1.5 tonnes (with the Principal out of it!). Draw a diagram to compare the number of cars with your pool. The average weight of the children in the school is 30 kg (you don't have to weigh everyone). Compare that with the pool. What did you learn about measuring the weight of 'heavy' things?
 * Pool your thoughts**

Farmers, gardeners and schools kids take great interest in the weather, especially the wet parts of the weather. In all parts of the country the rainfall is measured and these figures are used to decide on crop planting, harvesting, power generation, or whether you take a rain coat etc. But did you ever stop and think about how much rain falls on you? No! Well now is your chance. Go to [] and download the spreadsheet that gives mean rainfall totals for many places around NZ. Pick one close to you or use records that are kept locally. Now mark out an area 10 metres square on the court and, using the spreadsheet and water volume and weight things you have already worked out in earlier challenges find out the total weight of the rainfall on that patch of court in a year. The Wairarapa Valley (use Masterton's rainfall) is about 100 km long and 10 km wide. I wonder what the water that fell on the whole valley in one year weighed? How many school swimming pools is that? Next time it rains have a think about how [|heavy] clouds are! [|Heavy air?] A bit more on [|why clouds float]. 
 * A swimming pool fell on my head!**

How might you measure the weight of water in a river?

Have a wee look at [|this] 750000 gigalitres is quite a lot. This is a very large swimming pool on the move. That is a pretty big iceberg. [|Here is tiny one.] Can you see the person standing on it? Thoughts?
 * There is a lot of water in the pool?**

Let's see what heavy things we can find. You might like to use the book 'How Big Is It?' as a place to start. Other sources of information will be Wikipeadia and the 'Guinness Book of Records' Here are some to explore. Try these sites. [|One] [|Two] [|Three] [|Four] Did you get different information from each site? Write up some notes about Beelzebufo that you can share with others.
 * My big explorations**
 * How would you like to meet Beelzebufo?**

What other large / heavy things can you find in the natural world especially from New Zealand. How about the Gigantic Squid at Te Papa or Tane Mahuta or the Kakapo or the Giant Weta, the Moa or the Kiwi's egg. Write an article that you can share with others. Include at least one illustration.
 * Your challenge**

Check out this machine . What other heavy things can you find?
 * How about heavy things in the Man made world.**

Ok so here is another big piece of machinery - maybe they are boy's toys but this is something special.

[|Big and small things] to talk about from the National Geographic


 * You think these are big** - check out the [|largest recorded on land slip]. Try and imagine how big that is. [|A bit more about it.]