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A processed food is anything we eat that we’ve changed on purpose in some way from its natural state. We call the process that causes the change ‘food processing’, and we’ve been doing it for thousands – even millions – of years.

Simple processing includes things like bagging, washing and cutting up food.  This doesn’t change it too much. Heavier processing includes cooking, adding preservatives, sugars or salt, combining foods, or changing their textures. It is more likely to change the properties of a food and also how good it is for us. When people talk about “processed foods” they usually mean heavily processed ones like snacks and convenience foods.

Washing, cooking or chilling food to kill harmful bacteria are examples of processing which can make food safer. Adding lots of sugars, fats, or salt are examples of processing which can make it less healthy.  We need to balance the helpful and harmful.

There are different degrees of food processing

We can think of processed foods as falling on a scale depending on their level of processing:

Simple processing keeps most of a food’s natural physical, chemical, and nutritional properties. We do it when we wash, clean, bag and cut up fresh food.

Minimal to moderate processing changes more food properties. It includes blanching*, cooking, freezing, drying, juicing and extracting, crushing, mincing, pickling and canning; it’s also processes like pasteurising, refining and milling. It can involve adding ingredients like fats, oils, sugars and sweeteners, salt, flavours, and preservatives; or using processes like baking to combine foods and change their structure.

Heavy processing involves even more ingredients (including additives: emulsifiers, colours, and stabilisers) and more complex chemical or physical processes (like adding hydrogen to saturate unsaturated fats, water to plump up bacon, or carbon dioxide to make fizzy drinks). This further changes the structure, taste, time it will last, texture, and nutritional value of foods. It creates the products most people think of as “processed foods”: crackers, snacks, cakes, biscuits, deli meats (like salami, ham and bacon), cook-in sauces, breakfast cereals, soft drinks … all the way up to convenience foods and ready-to-eat meals.

Why do we process foods?

To help ourselves. Simple or minimal processing makes foods cleaner and easier to eat and transport. We also process foods to make them suitable or safe to eat (e.g. milling grain, boiling raw potatoes, pressing oil, pasteurising milk, or cooking meat). Some processes (like blanching*, canning and freezing) preserve foods so we can enjoy them safely at our convenience and out of season. But we also process foods to make them more appealing – whether by adding sugar, fats and salt for taste, removing some fats, swapping artificial sweeteners for sugars, removing fibrous husks, adding or removing caffeine, adding vitamins or minerals, altering textures, or using preservatives to make foods last longer.

Sometimes processed foods may not be the best choice

Some processed foods encourage us to eat more salt, sugar and fat (especially saturated) than we need, and various substances about which we know very little. Our understanding of what’s in a food usually decreases as processing increases, so it’s harder to make healthy food choices. Processing can also alter concentrations of key nutrients.

Sometimes processed foods are helpful

However, many processed foods have a place in our lives – and not just because they keep foods safe from unwanted bacteria. If someone is busy, being able to use frozen, pre-cut, or washed fruits and vegetables for a meal could make the difference between eating them or deciding not to; canned foods like cooked kidney beans or tuna provide nutritious foods we might not have time to prepare safely or at all; and affordable tinned foods like tomatoes, fruit salad and pineapple can add useful amounts of vitamin C to our diet.

*Briefly putting food in boiling water or steam to stop the enzymes that break it down from working.

What is the Liver?
The Liver is the largest solid organ in the body. It grows as we grow until, when we are adults, it has reached the approximate size of an American Football. It can be found on the right side of the body, just under the rib cage. Blood constantly flows through the liver to be cleaned and processed, and the liver holds approximately 13% of the body’s entire volume of blood at any one time.

What does the Liver do?
The Liver has over 500 functions, but some of the most important ones are:
• Processing digested food and absorbing useful nutrients into the blood.
• Removing harmful substances and waste products from the blood.
• Breaking down food and converting it to energy, especially heat.
• Storing energy as glycogen, ready to be used when it is needed quickly.
• Making bile, which is stored in the gallbladder until it is needed in the blood to help absorb fat from food.
• Fighting infections within the body, and cleaning bacteria from the blood.
• Storing iron, vitamins, and other essential chemicals until they are needed.
• Making enzymes and proteins to be used elsewhere in the body.

What are the Kidneys?
We each have two Kidneys. They sit under the ribcage – one on either side of the spine – and filter the blood that they receive from the renal artery.
Their most important task is to filter waste. They also filter enough water from the blood to keep the fluid levels in our bodies balanced, and combine this excess water with the filtered waste to make urine. The urine travels through the ureter to the bladder, where it is stored until we go to the toilet.

Our Kidneys are also involved in:
• Keeping levels of certain minerals in the blood such as potassium, sodium and phosphate stable.
• Producing hormones that make red blood cells.

What is the Pancreas?
The Pancreas is a long, flat gland about 12 cm long that sits behind the stomach. It has two main jobs:
• Making enzymes which digest fats, carbohydrates and proteins, and sends them to the small intestine through the pancreatic duct. The nutrients can then be absorbed into the blood.
• Making hormones: most importantly insulin, which controls and regulates the amount of glucose (sugar) that the body can store and use. When the Pancreas cannot make enough insulin, the person may develop diabetes.

Being part of a team
When we are part of a group of people who share skills and work together to achieve a common goal, we are part of a team.
Sharing ideas and collaborating with others enables us to work creatively together. When each team member contributes, we can benefit from a wide range of strengths and skills. We can also help other people to be a good leader, by being a good team member.
Skills involved in being a good team member include:
. Reliability – do what you say you will do
. Communication – listen to others, and respond clearly and calmly
. Flexibility – be prepared to adapt when circumstances change within the team
. Focus – concentrate on your own work, and let others concentrate on theirs
. Being Respectful – of the roles and abilities of other team members

Types of Teams
When we think of a team, we often think first of a sports team, but a team is really any kind of group that is formed for a specific purpose. Some examples are:
. School student council
. School crossing patrollers
. Library monitors
. Class maths group

Being a Leader
Just as being a strong team member is crucial to the success of the team, so is having good leadership. A leader helps a team to stay on task, as well as making sure that all team members are valued and effective. Good leaders are positive and inclusive, not bossy and judgemental.
Although some people appear to have ‘natural’ leadership abilities, in actual fact, leadership skills can be learnt by anyone.
Good leaders:
. Help everyone to understand and ‘see’ the goal
. Motivate the team to keep going when things get hard
. Know how to listen to others, and communicate well
. Ensure that all team members feel valued
. Lead by example: be hardworking and reliable themselves
. Know how to encourage, not dominate, the team
. Are respectful of others and their abilities
. Treat all team members fairly
. Are prepared to take responsibility for the team and the outcome
. Can make difficult decisions when needed

At school, and in the community, it is important to take opportunities to lead – perhaps starting with small groups and projects. Leadership experiences can be very rewarding.
With a good team and good leadership, great things are possible. Whether the goal is to write and perform a play for the class; to plan and organise a school disco; or to compete in a sports tournament, teams need the participation and commitment of each team member to be truly successful.

The skeletal system is the name for all the bones and joints that make up the internal structure of our body.  There are 206 bones in the human body. 

What are bones made of?

  • The outer layer of a bone is called the Periosteum. It is a thin, strong layer containing nerves and blood vessels which nourish the bone.
  • Compact Bone is the shiny white layer of bone that we imagine when we think of a skeleton. This layer gives the bone its strength and structure.
  • Cancellous Bone, also known as spongy bone, is the spongy-looking layer of bone underneath the Compact Bone. This is designed to be strong but light, so that we can move around easily.
  • Protected in the centre of some bones (such as the femur, or thigh bone), we can find Bone Marrow. This is where our body makes blood cells.


What do our bones do?

  • The skeleton is the scaffold for our bodies. It provides a stable, strong structure for our muscles to attach to, and gives us shape.
  • Muscles and bones act together so that we can move. They act as levers – for example when we lift things, or kick balls – without too much effort.
  • Our organs are protected by our skeleton. For example: the skull protects our brain, while the rib cage protects our heart and lungs.
  • Blood cells are produced deep inside flat bones (such as the skull or hip bones) and long bones (such as thigh or arm bones).
  • Essential minerals and substances are stored in our bones for use when needed. The most important of these is calcium.
  • Bones change and develop as we grow. When we are born, we have about 300 bones.  As we grow, some of them grow together (fuse).  Other ‘bones’ are made of a substance called ‘cartilage’ when we are born, and slowly absorb calcium and turn into adult bone as we grow up.  This process happens at a certain rate, and is completed by the time we are 25 years old.  This explains why archaeologists can sometimes tell how old a person was, just from their skeleton.
  • Bone cells release a hormone that regulates blood sugar and fat deposits.

What are joints?

The point of contact between two bones is called a joint.  We have several different types:

  • A Fixed joint doesn’t move at all. A flat plate in the skull fused to another plate is an example of a fixed joint.
  • A Synovial joint is the most common type in our body. The space where two bones meet is covered with a kind of capsule which holds liquid called synovial fluid. This fluid acts like oil to stop friction and allow the bones to move.
  • A ‘hinge joint’ is where the bones can only move in one direction, such as the elbow.
  • A ‘ball and socket’ joint can move in many directions. The shoulder and the hips are ball and socket joints.

Public Domain images courtesy of WPclipart.com


KidsHealth.org, Your Bones, October 2012.  Retrieved from:

http://kidshealth.org/ 20 March 2015

InnerBody.com Skeletal System, n.d. Retrieved from: http://www.innerbody.com/image/skelfov.html  20 March 2015

With support from       JSB Education

LET NZ 20 March 2015

My individual characteristics, qualities, and abilities make up my identity. My identity makes me special and unique.

How does identity develop?

When we are first born, we are not aware that we are separate and individual beings. From about the age of two, we begin to understand the concepts of ‘I’ and ‘You’. At about 18 months, we are able to demonstrate our ability to be self aware when we can recognise ourselves in a mirror.

From about 3 years of age, we start to form a sense of who we are. This is called self concept, and it develops as we make our own decisions and act on them. This new independence helps us to learn about ourselves and our capabilities. We start to identify ourselves by how we feel about our abilities, for example: ‘I am good at running’. We see ourselves in concrete terms, such as how tall we are, or what colour our hair is.

Middle childhood (from about the age of 7 till puberty), is a time when we are very aware of the people and the environment around us. As we try more activities and gain more skills, we compare ourselves with our peers and realise that we are more competent at some things than at others. This helps us to form a well-rounded sense of ourselves. As we compare our capabilities (sports, academics, social skills) with others around us, we develop a concept of self competence. Having positive and encouraging role models will also help us to develop a healthy sense of self worth.

During adolescence, we begin to establish our adult identity. This includes re-evaluating what we feel about who we are, and retaining or rejecting ideas and values from our childhood. We are free to experiment with different personalities and roles. We are now capable of abstract thought, (ideas and concepts that are not concrete) which means that we can think of ourselves in terms such as ‘loyal’ or ‘kind’. It also means that we can imagine a future for ourselves, and make new use of our skills and abilities to help us to plan and prepare.

Identity Workout

If we think of our sense of identity as a muscle, then we can think about things that will give it a workout and help it to be stronger and healthier.
• Positive People – who are my role models? How do they do encourage me?
• Resilience – when things go wrong, can I try again?
• Success – what am I good at? How does it make me feel?
• Community – what are the values of my school/culture/family/country? What do they mean to me?
Thinking about who we are and about the influences that surround us helps us as we mature and develop our sense of self, so that we can make positive decisions about our lives for the future.

YourDictionary.com ‘Identity’ n.d. Retrieved from http://www.yourdictionary.com/identity 11 June 2015

Princeton University ‘The Development of Children aged 6 to 14’ 1999. Retrieved from:
http://www.princeton.edu/futureofchildren/publications/docs/09_02_02.pdf 24 June 2015

Education.com ‘Identity Development’ 23 December 2009. Retrieved from:
http://www.education.com/reference/article/identity-development/ 24 June 2015

With support from JSB Education

LET NZ 13 July 2015

My brain is protected inside my skull by cerebrospinal fluid which acts as a shock absorber. This cushions the brain from damage caused by everyday bumps or knocks.
This cushioning is needed because, inside my skull, my brain is soft and squishy – like ripe avocado or warm butter. If my head is suddenly hit against something hard, the brain may be ‘bounced’ against the inside of my skull, and brain tissue can be stretched or bruised. In serious cases, the brain may even bleed.

How could my brain get an injury?
The most common causes of injury to the brain are:
• falling
• car accidents
• bicycle accidents
• sporting accidents (eg a rugby tackle, or being hit by a cricket ball)
• being struck or hit by another person
• illness (eg meningitis or seizures)
• lack of oxygen (near-drowning or suffocation)

How can a brain injury make me feel?
People with brain injuries can have many symptoms. They may include:
• headache
• vomiting
• tiredness
• loss of memory
• inability to concentrate
• moodiness / irritability
• changes in behaviour or personality
Other effects of an injury depend on the part of the brain that is damaged. For example, problems with hand/eye coordination may happen if a particular part of the parietal lobe (area of the brain just behind the top of the head) is injured.

How can I keep my brain safe?
There are things I can do to protect my brain from injury. They include:
• wearing helmets for activities such as riding a bike or skateboarding
• always wearing a seatbelt in a car
• being careful in high or dangerous places where there is a risk of falling

This week we have 3 research tasks that you could complete;
1. Research and find five amazing facts about our brains?
2. Research into some of the medical conditions that can affect the brain?
3. Research the different parts of the brain and create a diagram to show these areas.

Muscles make all our movements possible. We have over 600 muscles in our body. Without them, the rest of our body systems would not be able to function.
We have three different types of muscles in our bodies:
Smooth muscles, also called ‘involuntary’ muscles, are controlled by our brain. We can’t consciously control these muscles. Smooth muscles keep our crucial body systems working. For example, the muscles that move our food through the digestive system, or focus our eyes as we look around, are smooth muscles.

Skeletal muscles are the muscles that we can control. They are also known as ‘voluntary’ muscles. Tough cords of tissue, called tendons, attach skeletal muscles to our bones. When we decide to make a movement, we send a message from our brain to the muscle we want to move. The muscle contracts, and pulls the tendon and bone with it – and that is how we move. A message can travel from the brain to the muscle at speeds as fast as 430 km/hr!

The gluteus maximus (buttock) muscles are the strongest muscle in the body. They enable our legs to straighten when we walk, run, or climb. They are also the muscles we use when we stand up from a sitting position.

Cardiac muscle is the thick, strong muscle that makes up our heart. It is considered an involuntary muscle because a special group of cells stimulate the heart to contract and pump blood around the body – all day, every day.

Muscle is a soft tissue made up of fibres. The fibres are built from cells which contain protein filaments that slide over each other to make a contraction.
Our skeletal muscles often work in pairs or groups, so that our movements are smooth and coordinated.
For example, the biceps muscle contracts to bend the arm, while the triceps muscle contracts to allow it to be straightened.

Major Muscles
• Because there are so many skeletal muscles in your body, we can’t list them all here. But here are a few of the major ones:
• In each of your shoulders is a deltoid muscle. Your deltoid muscles help you move your shoulders every which way — from swinging a softball bat to shrugging your shoulders when you’re not sure of an answer.
• The pectoralis muscles are found on each side of your upper chest. These are usually called pectorals or pecs, for short. When many boys hit puberty, their pectoral muscles become larger. Many athletes and bodybuilders have large pecs, too.
• Below these pectorals, down under your ribcage, are your rectus abdominus muscles, or abdominals they’re often called abs for short.
• When you make a muscle in your arm, you tense your biceps muscle. When you contract your biceps muscle, you can actually see it push up under your skin.
• Your quadriceps or quads, are the muscles on the front of your thighs. Many people who run, bike, or play sports develop large, strong quads.
• And when it’s time for you to take a seat? You’ll be sitting on your gluteus maximus – the muscle that’s under the skin and fat in your behind!

Self-Esteem is a term we use to describe how much we value ourselves.
Why is it important to have a healthy self-esteem?
When we have healthy self-esteem, we understand that we are valuable and likeable. Having self-esteem is not bragging or feeling better than others, but is the ability to accept and appreciate ourselves and our capabilities.
Self-esteem helps us to deal with everyday mistakes and problems, and learn from them.
When our self-esteem is healthy, we have the courage to try new things and the confidence to make our own decisions.
How can we improve what we feel about ourselves?
One useful strategy we can use to improve our self-esteem is to use ‘affirmations’. Often, people with low self-esteem have negative thoughts running through their heads, and may literally ‘talk themselves’ into believing that these things are true.
Instead of negative thoughts, using positive phrases remind us that we are valuable and worthwhile people.  Some examples are:

  • I care about myself.
  • I am a good friend to myself, and others.
  • I accept myself just as I am.
  • Life is good, and I like being a part of it.
  • I respect myself and others

How can we help other people improve their self-esteem?
Encouraging our friends and classmates, and celebrating their successes, will add to their self-esteem and help them to feel valued and appreciated.
When we help those around us to feel good about themselves, we help to build a supportive and positive environment within our families and our classrooms.
For more information CLICK HERE.

Digestion is the process by which food is broken down into its smallest parts, which can then be absorbed into the bloodstream and used by our bodies to grow, repair, and function.

How do we digest food?

Food is broken down in the mouth by our teeth as we chew.
The mouth also contains saliva, which is a watery fluid that moistens and lubricates the food.
Saliva also contains amylase, which is a digestive enzyme that starts breaking down starches in the food.
The swallowing reflex moves food into the oesophagus, where involuntary muscle movement called peristalsis moves the food down into the stomach.

Within the stomach the food is churned and mixed with gastric juice, which is produced by cells within the stomach lining.
Gastric juice is highly acidic, and also contains enzymes which start to break down the protein in the food, eventually reducing it to a creamy paste known as chyme. At the bottom of the stomach, the chyme moves into the small intestine, or duodenum.
Juices from the pancreas and bile from the liver enter the duodenum and help to lubricate the partially digested food as it moves through the gut. Large molecules within the chyme are broken down into small molecules so that they can be absorbed into the bloodstream.
The enzymes that we use to break down food are made in our cells, and we make different ones to break down specific types of food, for example – carbohydrates or proteins.

The small intestine is where nearly all of our food is absorbed into our body. Once broken down into smaller molecules, the nutrients can be absorbed through villi, which are tiny structures shaped like fingers protruding from the lining of the small intestine.
Villi increase the available surface area so that as many molecules as possible can be absorbed and carried into the bloodstream.

By the time the digested food products have reached the end of the small intestine, most of the useful nutrients have been removed, and only indigestible elements remain.
The large intestine removes water, and forms and stores the faeces. A large amount of bacteria (more than 500 species) are present in the large intestine. These help to recover any remaining nutrients from the food, and also make some vitamins – such as Vitamin K – for the body to use.

As undigested material accumulates in the rectum, it stimulates a response that leads to the evacuation of the waste through the anus.
How do we get energy from food?

Once food is broken down by the digestive process and enters the bloodstream, the molecules from the nutrients it contained travel in the blood to every cell. Inside the cells, they are used to give us energy, as well as to grow and maintain our bodies.

What is a mindset?
A mindset is a belief or an attitude that we have about something. Some mindsets are negative (“I am not good at singing”) – but they can also be positive (“I am kind to animals”).
Sometimes, our mindsets are part of the culture and history of where we live, and can even change with time (“Women can’t be doctors!”).
Mindsets may be based on stereotypes or generalisations, and not fact – for example, that: “People who wear glasses are smart” or “Boys are better at running than girls”.
How can I change my mindset?
Understanding that we have the ability to think differently about ourselves and those around us can help us to create new opportunities to grow and learn new skills.
Some ways to do this are to:
• Be curious and open-minded in our attitudes.
• Be open to learning new skills, and enjoy the challenge.
• Learn from our failures – they can teach us even more than our successes.
• Focus on the learning process, not just the achievement.
• Remember that the brain is like a muscle – the more we use it, the more it grows
• Always keep trying. Don’t give up!
Do I have a ‘Fixed Mindset’ or a ‘Growth Mindset’?
Many people have what Stanford University Professor Carol Dweck calls a ‘Fixed Mindset’. People with Fixed Mindsets believe that their talents or intelligence are ‘given’ to them, and can’t be extended or changed. They may see a test result as measuring their actual intelligence rather than simply being a snapshot of their skills at that moment in time. Focusing solely on the end result can make it easy to become discouraged when things seem hard, or don’t go well.
In a ‘Growth Mindset’, people believe that they can grow and develop their talents through time, effort, and dedication.
This means that we can learn, or get better at, just about any skill that we choose. As we practise a new skill – either a mental one such as learning a language or a physical one such as basketball – we create new links between synapses in our brains.
As we repeat these skills again and again, we strengthen these connections, and our abilities ‘grow’. Sometimes we use this to get better at something we are already skilled at, such as maths; but we can also learn something entirely new to us, such as ice skating.
When we understand that success comes from effort and practise, we can see how important it is to keep going, even when it seems difficult. Sometimes, things may go wrong. We may even fail at something we tried to do.
However, having a Growth Mindset means that we can understand that failures or changing circumstances are part of life, and don’t necessarily stop us from achieving a goal or from being successful. We can adapt. We have become resilient.
When we have a Growth Mindset, we learn to value hard work in others, as well as in ourselves. We can cope with disappointment and are able to make new plans to achieve our goals.
Thinking in a Growth Mindset encourages us to be independent thinkers in charge of our own learning, as well as giving us the freedom to enjoy the process of learning itself.