Your body has gone probably 8 hours or more without food or drink. You can't run a car without any gasoline and you can't expect your body to run without fuel either. Breakfast supplies your body the energy it needs to function. Breakfast does not have to take much time. Grab a baggie of dry cereal and a carton of juice while walking to the bus stop.
Fruit is natures answer to fast foods.
Apples, pears, bananas are all quick and easy to take along. Try leftover pizza or peanut butter on toast or a tortilla and cheese wrap for a quick, nontraditional option.