Back in the day, thermoses were all the rage. Learn how they worked!
These days kids have Styrofoam to keep soup hot, but back in my day, we all had thermoses. One of their drawbacks was that since their insides were made of glass they were pretty easily broken when dropped. The popping sound they made when they broke was cool to kids, but then we weren’t the ones who had to buy a new one. Learn more on this Moment of Science.