Well this was pretty fun. In answer to your question though, we didn't really learn much about Prime Ministers of UK in school. It was all about the Kings and Queens of (mostly) England and France.

They were pretty much all named Phillip, Edward, Charles, and Henry. They were all petty and liked to kill people after rousing games of palace intrigue.

Most in of the Prime Ministers Americans know are going to be Thatcher onward. Oh, and Chamberlain. Oh, and the first would have been mentioned.... sounds like, Prime Minister Tadpole? Or something.