How much food do i send my child to school with?

I got to talking to a mummy friend today about lunch box capacities and it got me thinking about the question "how much food should i send my child to school with?". I started to wonder about how to approach this and hopefully find an answer, this answer will obviously vary slightly from child to child depending on their age and appetite.
Our children spend the school hours away from us, this in most schools is around 7 hours, so if there are approximately 14 waking hours in the day (allowing 10 hours of sleep at night), the school hours will amount to around 50% of our children's 'eating time' being spent away from us. This means that approximately 50% of what our child needs in a day will be consumed at school. In our home we have breakfast, school lunch, afternoon tea and then dinner or we will have an early dinner and then an evening snack. To me this means that they need to be having a variety of foods that are healthy, nutritious and filling. Remember my food philosophy is all about moderation (you can check back on that post here), however i did find some information on the Eat for health. gov website that will help me break it down and give you a little bit of an idea. I am going to focus on children aged 4-8 as this is the demographic that my children are in currently.
This is what they should be having:

Children aged 4-8  

(Serves per day)

• Vegies, legumes/beans:  4 1/2  
• Fruit: 1 1/2 
• Grains: 4 
• Meat etc., eggs, nuts, seeds : 1 1/2  
• Dairy*: 2-3

   * This website says to feed your children reduced fat dairy, DO NOT feed your children reduced fat anything. Fat is good, sugar is not.

So this is what they would be having approximately at school

• Veg etc.: 2 1/4
• Fruit 3/4
• Grains: 2
• Meat: 3/4
• Dairy: 1- 1 1/4

What is a serving size?

Vegies, legumes/beans

A standard serve is about 75g (100–350kJ) or:

• ½ cup cooked green or orange vegetables (for example, broccoli, spinach, carrots or pumpkin)
• ½ cup cooked dried or canned beans, peas or lentils (preferably with no added salt)
• 1 cup green leafy or raw salad vegetables
• ½ cup sweet corn
• ½ medium potato or other starchy vegetables (sweet potato, taro or cassava)
• 1 medium tomato

Fruit
A standard serve is about 150g (350kJ) or:

• 1 medium apple, banana, orange or pear
• 2 small apricots, kiwi fruits or plums
• 1 cup diced or canned fruit (no added sugar)

Grains

A standard serve is (500kJ) or:

• 1 slice (40g) bread
• ½ medium (40g) roll or flat bread
• ½ cup (75-120g) cooked rice, pasta, noodles, barley, buckwheat, semolina, polenta, bulgur or quinoa
• ½ cup (120g) cooked porridge
•  ²/³ cup (30g) wheat cereal flakes
• ¼ cup (30g) muesli
• 3 (35g) crispbreads
• 1 (60g) crumpet
• 1 small (35g) English muffin or scone

*Grain (cereal) foods, mostly wholegrain and/or high cereal fibre varieties

Meat etc., eggs, nuts, seeds
A standard serve is (500–600kJ):

• 65g cooked lean red meats such as beef, lamb, veal, pork, goat or kangaroo (about 90-100g raw)
• 80g cooked lean poultry such as chicken or turkey (100g raw)
• 100g cooked fish fillet (about 115g raw) or one small can of fish
• 2 large (120g) eggs
• 1 cup (150g) cooked or canned legumes/beans such as lentils, chick peas or split peas (preferably with no added salt)
• 170g tofu
• 30g nuts, seeds, peanut or almond butter or tahini or other nut or seed paste (no added salt)*

Dairy
A standard serve is (500–600kJ):

• 1 cup (250ml) fresh, UHT long life, reconstituted powdered milk or buttermilk
• ½ cup (120ml) evaporated milk
• 2 slices (40g) or 4 x 3 x 2cm cube (40g) of hard cheese, such as cheddar
• ½ cup (120g) ricotta cheese
• ¾ cup (200g) yoghurt
• 1 cup (250ml) soy, rice or other cereal drink with at least 100mg of added calcium per 100ml

(all of this information came from here)

This all seems like a lot to take in but i'm going to break it down into an example school lunch menu for you ( I haven't worked out the exact amounts in each one but you get the idea):

1/4 cup carrot sticks with hummus dip

1 apple cut into slices (skin on)

A chicken and spinach wrap

Squeeze pouch of yogurt

OR

A piece of corn on a bed of spinach

A mandarin

An English muffin pizza with ham, cheese and no added sugar tomato sauce.

Sweet potato chips.

As I mentioned earlier, all children have different size appetites so you will need to adjust this to what you think your child needs. You can always throw an extra banana, apple or container of carrot sticks in their bag as a 'just in case' snack. If your children are getting this type of food at school, and then the rest of their serves of the essentials at breakfast, afternoon tea and dinner time they should be functioning at their very best. In my opinion their sugary 'treats' should be saved for the weekend, by all means add in a 'no added sugar' sweet treat to their lunch box ( i do). There are some great recipes out there. But, again you will need to do what works for your family, i did mention that we are on a journey to cut right back to very minimal added sugars so i will encourage you to also not regularly have these foods in your children's lunches and offer better choices as alternatives.