How Popcorn Pops

The kernels are a seed and when you heat it up, the inside turns into steam. The steam pushes on the inside of the shell. The shell explodes and turns into popcorn that you can eat(diagram included in published work).

Roman (Year 3)

How Popcorn Kernels Turn Into Popcorn

There is a tiny bit of water in the kernel that heats up and steams and tries to boil, but the hull traps it in there. When the pressure gets too great, the kernel turns inside out and turns into popcorn. (diagram included in published copy) Jamie (Year 3)

How Does Popcorn Pop?

This is how popcorn pops. When the heat goes on the seed it makes steam in the seed and it gets really hot, like a classroom full of children! Then it explodes and turns inside outbecause it is too much for it. It turns into a fluffy piece of yummy popcorn. (diagram included in published copy) Harry (Year 4)

Popcorn

The inside of the popcorn seed boils until it is very hot, then the water turns into steam. The steam really wants to get out of the popcorn seed. It pushes and pushes and pushes until it explodes and it turns inside out. Then it is fluffy creamy-white popcorn. They are very different shapes and sizes - some are bumpy, some look like bumble bees and some look like ballerinas. ( diagram was included on her published copy) Georgie ( Year 4)

How Popcorn Pops!

The seed has a little water in it and the heat turns the water into steam. The steam is kept in the seed. The hull (shell) traps the steam and the steam pushes and pushes until the power is so great. The seed turns inside out and the starch turns into fluffy white popcorn and the hull is soft. ( Diagram included in published copy)
Otis (Year 3)

The Physical Properties of Popcorn

WALT... find out about the physical characteristics of unpopped and popped popcorn

We looked at unpopped and popped popcorn and answered these questions as a class.

Questions:
What colour is it?
What size is it?
What shape is it?
What does it feel like?
What does it smell like?
What does it taste like?
Have the physical properties of the popcorn changed?
If so what are the differences?

This is how popcorn pops!

Did You Know?

• Popping corn is different from ordinary corn; the kernels are harder and drier.
• Each kernel has a hard, yellow outer layer of starch called pericarp.
• Popcorn is made up of starch, fibre, vitamins and water.
• The white fluffy stuff is the starch that’s been cooked by the heat.
• The pericarp is hard fibre and fibre makes your poos float.
• When popcorn explodes it can expand up to 30 or 40 times its original size.
• People have been eating popcorn for about 7000 years.
• The oldest known popcorn was found, still fluffy white in a bag attached to the belt of a mummy in Chile.

Making Crystals

The reason we grew crystals was to see how liquids can be changed into solids. And these ones could be eaten because they were made of sugar!
We have a lot of children wanting to make these at home so here are our instructions.

In a pot, heat at least three cups of sugar together with one cup of water. I know it seems like a lot of sugar, but you want to dissolve as much sugar as possible into the water. While stirring, bring the sugar solution to a boil. Remove the pan from heat and, if you want, add a few drops of food colouring.

While the sugar solution is cooling, get a jar ready for growing the crystals. Hang a string or popsicle stick into a glass or jar. Don't let the string or stick touch the sides or bottom of the container. Pour the sugar solution into your jar. Grow your crystals somewhere they won't be disturbed. Crystals will start growing in a day or two.

Be patient - crystals will form as the water evaporates. If you see crystals growing on the top of the container, break them off and eat them or throw them away. If crystals start to grow on the sides or bottom of the container, just transfer the crystals and crystal solution to a clean glass or jar.

What is the difference between a solid, liquid and gas?

Gas

Gas

Run in place very fast for a minute. Do you notice how hard you are breathing? What you are breathing is oxygen? You need oxygen to live. That's why you can only hold your breath for a certain amount of time.

You can't see oxygen. It's invisible. It is a gas. A gas is matter that has no shape or size of its own. Gases have no colour.

Gases are all around you. You can feel gas when the wind blows. The wind is moving air. Air is many gases mixed together.

Liquid

Liquids

Milk is a liquid. Milk is liquid matter. It has a size or volume. Volume means it takes up space. But milk doesn't have a definite shape. It takes the shape of its container.

Liquids can flow, be poured, and spilled. Did you ever spill juice? Did you notice how the liquid goes everywhere and you have to hurry and wipe it up? The liquid is taking the shape of the floor and the floor is a limitless boundary (until it hits the wall). You can't spill a wooden block. You can drop it and it still has the same shape.

What about peanut butter and jam?

You can spread peanut butter on bread, but peanut butter does not flow. It is not a liquid at room temperature. You have to heat peanut butter up to make it a liquid. When you or your mom makes jam, it is first a liquid. You have to put it in the refrigerator so that it becomes a solid. These are yummy forms of matter with properties of a liquid and a solid.

Solids

Solids

The wood block is solid. A solid has a certain size and shape. The wood block does not change size or shape. Other examples of solids are the computer, the desk, and the floor.

You can change the shape of solids. You change the shape of sheets of timber by sawing it in half or burning it.

eg from wood to smoke

Solids, Liquids, Gases

SOLIDS
• Keeps its own shape
• All particles are very close together

LIQUIDS
• Fills the shape of the container
• Particles are not close together

GASES
• Fills all the space around them
• Particles are not close together

Solid, Liquid and Gas

States of Matter

To begin the term we are going to look at Change of state. Our BIG IDEA for the year is 'Change'. Take a look at this YouTube video to see how the particles are arranged for solids, liquids and gases.

From Seed to Snack

Technology(Production & Process)
From Seed2Snack

What is a flow Chart?
In a flow chart items are organized in a sequence.
Flow charts have different uses:

They may be a chain of cause and effect, explaining a process (e.g.a popcorn seed to a popcorn snack)
They may organise past events in a time sequence, recounting what happened.
They may show a series of steps, forming instructions.
They may be a sequence of reasons,in an argument.

Many flow charts are combinations of chains, forks, and loops.

Why use flow charts in the classroom?

To plan an explanation, a procedure (instructions), a recount (such as a news story), a narrative, or an argument.
To summarise an explanation, a procedure, a recount, a narrative, or an argument.
Examples of topics that suit flow charts include the water cycle, life cycles, how products are made, where a certain food comes from, preparation for a debate, how machines work, and so on. Flow charts are one of the most useful visual texts in the classroom.

We looked at 3 types of flowcharts...
Cyclic
Forked
Linear
Today we used a linear flowchart to show how the popcorn is produced, from seed to snack

BIG Ideas about Popcorn

• Kernels contain starch and moisture


• When you heat the kernels, a change of state happens, in which the moisture changes into steam-this is a physical change


• The popping of popcorn is actually a small explosion which occurs when the pressure of the steam is so intense it bursts the tough outer coating of the kernel

Popcorn

A popcorn kernel is actually a seed. Like other seeds, inside it has a tiny plant embryo (a life form in its earliest phase). The embryo is surrounded by soft, starchy material that would give the embryo energy for growing into a plant. A hard, glossy shell protects the outside of the seed.
The soft, starchy material holds some water. When the kernel is heated to a high heat (200c), the water inside the kernel turns into steam. The pressure from the steam causes the kernel to explode. The soft starch inside bursts out at about 40 times its original size, turning the kernel inside out. This creates the fluffy white area of a popped kernel.
The ideal popcorn kernel contains about 14 percent moisture. If the popcorn is much drier, it will not pop. Popcorn kernels should be kept in a tightly sealed jar so that they will not dry out.

Popcorn Inquiry

On Monday Maria Gill visited our school.  She is a New Zealand author and we have lots of her books in our school library.  We learned about native birds and their predators and how we need to look after our special NZ native birds.  She chose ten children to represent the predators and the native birds.  Visit her website at   http://www.mariagill.co.nz/

Watch out Birds!  Predators on the Hunt!

Maria Gill - Author

Evie with one of the Native Bird Puppets