What to Eat Before a Game or Practice
First, the athlete should maintain a healthy diet every day, not just on game day, for overall well-being.
Now on game day...
I have always believed in a diet high in carbohydrates (avoid fats, grease) about 1-2 hours before game-time or practice (you need time to digest it). Players should eat enough to feel their hunger is satisfied, but not overeat or stuff themselves. If it is a larger meal (lunch or dinner), eat at least 2 to 3 hours before the game; if it is a snack (you already had lunch or dinner earlier), eat the snack 1 hour before the game.
Some kind of pasta is a good lunch or dinner choice.
Cereals and grains
Crackers, peanut butter cracker or peanut butter sandwich
Avoid dairy products high in fat. Low fat yogurt would be fine.
Adequate fluid intake is important before and during the game to avoid dehydration... but again, too much is not good medicine. In addition to water, sport drinks or fruit juices are good choices.
If your practices or games are late in the afternoon, right after school, make sure you eat breakfast and lunch that day. Some fruit like bananas or oranges one hour before the practice or game would be a good booster.