How do I use the sensor shield v4.0?

I'm doing a school project where I'm trying get tictactoe to work. My code isn't the greatest and the wiring is mostly aesthetic and not particularly practical. I came to the conclusion that I need 27 pins for all buttons and leds, but could only reach up to 19 with the analogs counted in.

My teacher gave me the sensor shield v4.0 and said it gave me lots of options but I can't seem to find the correct names for the new pins on the shield. some website called them digital(0-13) but those are the names of the standard pins that were usable without the shield.

What do I call the pins in the middle of the shield?
Is there an easier way of adding 7-8 pins without a shield?

Thanks in beforehand,

That shield does not give you any extra pins. It only gives the same Arduino pins but with different types of connectors. Perhaps you did not explain very well to your teacher what you need.

Why do you need 27 pins for tic tac toe? Are you thinking one button and two leds each for 9 squares? You could do that with 12 pins, arranging your led and buttons in a 3x3 matrix and scanning the board by row or column.