What should I write my twelve page (or more) essay on?

I am an eighth grade girl. I need to write a 12 page essay for history cl. I can do a biography, a history of something (like music or cellphones), a specific war or event (not the revolutionary war please - I'm doing a project on that for a different cl!). Pretty much anything I want from the time frame of 1800's to present day. I was thinking the Iraqi War, Eleanor Roosevelt, Women's right to vote, The Internet, or Inventions in the 1900s. Any other ideas or tips?