Honestly so many people will tell you to eat healthily, or to indulge in carbohydrates to keep your energy levels up. Sure, that's fantastic. If you're willing to have a bowl of fruit and yoghurt, then by all means go ahead. /pos My best advice is to just eat whatever makes YOU feel good. Nothing is more motivating than waking up and fuelling the day with your favourite cereal. Even if it's packed with sugar, majority of cereals have all the vitamins and nutrients you need (and with good reason, too). I think you are more likely to perform well if you start the day off with a bang and just eat something you enjoy rather than being calorie/energy conscious. You have more important things to worry about. Don't forget to drink something (be it squash or tea) to stay hydrated, and bring a bottle of water (no wrapping) with you into the exam. That's something that's ACTUALLY important. Good luck on your exams!!