A childhood belief about physics

When I was a boy, my dad took a test drive in a Volkswagen bus, just so that I could have the reward of a lunchpail in the shape of a VW bus. The prize included a small thermos bottle. I'd take the pail and thermos to school, the thermos filled with iced juice. I convinced myself that when the ice melted in the thermos, the resultant water would fill the thermos beyond its capacity and it would explode, sending VW bus shrapnel throughout the classroom, killing me and anyone else in its path. Each day, I was anxious for lunch to come so that I could drink the juice and defuse the ticking time bomb. After weeks of such dread, I confessed my concerns to my dad. He explained that water expands during freezing and contracts during thawing. To this day, I believe that his explanation was the inspiration for my career in science.