Type 'easy' or 'hard' to begin the quiz. Easy is a 15-degree grid, hard is a 10-degree grid. Then, try to name the SECOND LARGEST city in each grid square. To name a city, you must first click on the grid square to make it have a GREEN border. Then, type in the city answer for that square followed by a '.' (a period). You are given a score from 0 to 100 based on your answer's population compared to the 2nd largest city accepted in that square (100 being you named the 2nd largest city). If you guess the largest city it will be based on the ratio of the 2nd largest city's population to the largest.
At the end of the quiz the 2nd largest city will show in each unanswered square, and for those answered the 2nd largest city will be listed next to your score if you didn't answer it.
Quiz Takers 
What is the source for answers for Tanzania? I would imagine Iringa would be bigger then Ifakara for example.
http://citypopulation.de/en/tanzania/cities/
Um, I selected Germany and someone has a score of 29 (more than the number of letters available, but obviously also more than the number of letters in the alphabet)?
Bosnia & Herzegovina isn’t working for me. Selecting it in the drop-down menu just does nothing, and I have to refresh to choose another country.
fixed this.
Here’s an idea for a similar quiz. You’ve created one with the largest US cities for each census – how about the largest US cities for each letter of the alphabet for each census? Might be too labor intensive, but thought I’d throw it out there