Teenager school lunch idea?

DD is off to secondary school this year. We have been lucky the last few years as DD has been able to do toasties in the classroom. DD does not eat sandwiches much,without them being toasted so I need a few ideas for her lunch box. Some days she eats like two men and sometimes still like a 4 year old so difficult to predict how much she needs.
Also there is a canteen at the school which we have never had before. One of her friends is getting $10 a week to spend there - do you think that is reasonable?

$10 a week is reasonable, but may not buy lunch the whole week - most school canteens charge close to retail prices for things like snacks, but I know the local high school here does a $6 sweet chilli chicken wrap which is cheaper than cafes. What about a bento box style lunch? Containers with salad and finger foods that she can either eat all or some of and not spoil? My girls like to take carrot/celery/capsicum sticks to have with cheese and jatz and if they don't eat it all, I can use it the next day because it keeps pretty well.

My DD (@ high school) likes to take wraps, salads or even cold leftovers. We have these salad boxes with an insert for salad sprinkles, dressing & cutlery, so you can put anything in, really, and it still comes together nicely at lunch time. Just make sure you include enough calories (by including protein, nuts, oil-based dressing) or she will be ravenous. Another thing some of the girls at school eat are various combinations of fruit salad, yoghurt, muesli etc.

Would your DD be more inclined to eat sandwiches if they were on rolls, pitas or bagels? Worth a shot,

I haven't given my DD money each week for canteen but she gets pocket money so she can spend it at the canteen if she wants to.