Telephone was invented by Alexander Graham Bell in 1876 in Cambridge, Massachusetts. His first telephone message was “Mr. Watson, come here. I want you.” Children can learn more at: Telephone.
Robert Goddard fired the first liquid-fueled rocket in 1926 in Cambridge, Massachusetts. Prior to this launch, only solid-fueled propellents had been constructed. His work regarding different fuels and rockets became the foundation of America’s space program. Older children can see how liquid-fueled rockets work at: http://science.howstuffworks.com/rocket5.htm.