DISCLAIMER: I want to apologize in advance for (ab)using the Thermos (R) brand name, but I've never seen a generic name for this product, though I have seen the generic product, it just never registered.
Having said that...
Did you have a lunchbox when you were a kid? The old school metal ones with a thermos inside that had the built in cup/lid cover? They were cool, weren't they? I mean that literally, too. My kool-aid stayed cold all morning in that puppy. And my chicken noodle soup? You could burn your tongue at lunch if you weren't careful to eat your crackers while the soup cooled to edible temperature in the cup/bowl/lid.
Well, my girl doesn't have that problem. Why? Because some moron kid somewhere dropped a Thermos, the glass liner inside broke, and the idiot didn't notice the shiny silver glass shards or the tinkling noise it made and ate/drank from it anyway. Now they line them with metal.
Which DOES NOT WORK as well. Some days it barely works at all. You can still find a few glass-lined Thermos vacuum bottles, but they are all huge and meant for construction workers or whomever to carry coffee. Way too big for a lunch box.
So now my kid gets cold food. Or warm drinks. Or, my favorite problem with the metal liners... They create such a hard vacuum when you seal in hot food that she can't open it at lunch. Apparently the adult lunch monitors can't either. Yet I always can... (rant for another day)
Meaning my kid gets snacks for lunch and comes home starving crabby. Since the crabby is a semi-given at age 9, I could really do without the starving.
Please, please, BRING BACK GLASS LINED KID THERMOSES*!
(thermoses? thermosii? anyone know the 'correct' plural for this?)
(Thermos image courtesy of kaboodle.com, despite the watermark, lol...)