If you are losing, press Plus, and select "Quit". You can play again with same team with which you almost failed previously.
At the beginning of some matches, you will be given a quiz question, and will get experience points for answering it correctly. After you answer the question and enter the game, you can press Plus and select "Quit" to return to the calendar, where you can join the same game and repeat the same quiz for more experience points. Repeat this as many times as desired.