US City Grid 2nd Largest City Challenge
DirectionsType ‘easy’ or ‘hard’ to begin the quiz. Easy is a 5-degree grid, hard is a 2.5-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.
AK and HI are NOT included in this quiz as they often have grid squares with only one answer for this quiz.
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 do orange and red mean?
I believe that.
a) If you chose the largest city in the grid – your score is Pop(2nd largest) / Pop(1st largest)
b) If you chose something other than the largest city in the grid – your score is Pop(Your pick) / Pop (2nd largest).
c) You get a green box if your score is high (perhaps above 90?). You get an orange box if your score is decent (something like 70-90?). You get a red box for low scores (below 70?). I am not exactly sure of the score cutoffs – but I think it is a score based cutoff, rather than being based on rankings (so I don’t think you get a red because you chose the 5th largest or smaller, for example). This kind of scoring is most consistent with the results I have gotten – and would be relatively easy to implement.