For tiredness drink either peppermint or fruit tea. Seeing as neither contain caffiene, they won't make you more alert, and the feeling of them in the stomach is reminiscent of the mother's milk as a baby. The natural reaction for having just been fed in babies is to go to sleep, and that reaction doesn't go away. Hot choccie works, but not so well, seeing as chemicals in choccie powder can keep you awake. Trust me, I know
Every Saturday night, I drink fruit tea because I have choir the following morning. It really works!