If you translate it into English, it will become something like this:
A: A - Apple
B: E - Egg
C: G - Girls
D: S - spiderman ... and so on
I guess you must have got the point already. It's a fantastic way to train the kids spelling and to enlarge their vocabulary. Although they don't spell out the entire word, they do need to know the previous word and the last letter of it in order to continue the game. It's fun!
Hope you'll like it!
Rayme
Chiba, Japan