Originally Posted by CarrieMF
At 10 she can earn money to pay for new ones. I'd also stop using the reusable stuff for her until she replaced them & showed some responsibility. Get brown paper bags, use wax paper or parchment paper instead of plastic bags if you don't want plastic bags.
If she gets an allowance, I also wouldn't give it to her, using it to buy her a new lunch box and reusable containers. Alternatively, I'd give her extra jobs until she worked off the lunch box. I'd try to express to her the bigger picture--this is about respect for the environment, respect for others' work, and personal responsibility. I'd emphasize to her that if she can't take responsibility for a little lunch box, you'll be less likely to give her bigger responsibilities as well--walking to the park by herself, pets, an expensive musical instrument, that sort of thing.