Our family...2 adults, 2 kids (4 and 5 years), 3 cats, 1 dog and 4 chickens, we spend about $200/week.
I spend between $50 and $100 at coles or woolies per week, About $80/week at the markets on fruit and veg and about $100/MONTH on meat.
I buy meat in bulk and portion it and freeze it, i buy staples (flour, sugar, butter, rice, pasta, canned tomatoes etc) and make most of my stuff from scratch rather than buy pre-made, processed stuff...IMO this is where alot of wasted money goes.
Start making cakes/cookies/school lunch snacks rather than buying them. Make soups/stocks, used canned tomatoes and herbs for sauce bases rather than buying jarred ones.
If you have a little space out the back, set up a herb garden, parsley, oregano, basil, rosemary. This will save heaps on buying jarred sauces etc.