A lot of lunch boxes come with freezer blocks that you freeze overnight and place in the lunchbox in the morning. It will keep food cold until lunchtime.

Fridge to go

These days I see a lot of lunch bags ( such as Kmart, Target , Big W etc ) and they are small carry bags with insulated foil lining inside to keep the food cold or hot . I normally don’t use meat for lunches during hot summer as I don’t trust meat in any outdoor condition . The bags come in lots of colours and design for the kids as well to make it fun looking .

I use SMASH insulated lunch boxes and little ice bricks. They also have insulated water bottle covers my kids find great.

thanks for posting this question. I just read these answers to get some ideas.

Freeze a yoghurt stick or a Prima drink and put into an insulated lunch bag. This will generally keep everything cool for most of the day and can be eaten/drank too.

buy one that you can wipe out at least! a lot of these types of bags will get wet and the kind of material that they are made from, will go mouldy quickly. Maybe just invest in a lunch block to freeze or freeze a popper

Freeze a new dish sponge (fill with water but not too much) then freeze. Place in a ziplock bag into the lunch box! Works a treat

I always use a small freezer brick-does a good job of keeping food cool.

For your yougart you can buy a tub wich is frozen and you can put your yougart into i thik it sold at spotlight,

I have always just used a small freeze brick.

I have smash freeze bricks which I bought it from K-mart. But I have been freezing yoghurts and cheese and putting them in the lunch box. So I haven’t used the freeze bricks.

I use an insulated lunch box instead of a plastic one and I have a smash freeze brick I picked up from my local Coles. In the summer I usually send the stuff frozen as otherwise it goes off fairly quickly, however in winter there is no need. I just put the freezer brick in the lunch box with the food.

Most mums I know ( I am a school teacher) freeze the yoghurt and put it in their lunch box and by snack or lunch it is still cold but unfrozen. Insulated lunch boxes are great with keeping this and other things cool in the lunch box. You can still put a cool pack in if needed but generally a frozen yoghurt will do the trick