Personally I eat a piece of fruit, have a scoop of whey, and eat half a cup of uncooked oats. I try to eat it at the same time every day and hit the gym at the same time. This gives me the best chance to "feel right". I know what I have to do at the gym and then I do it with confidence. Mental toughness is the key to focus.
You have the choice between focusing or being distracted.
So long as you have proper nutrition, get proper sleep/rest, and you stay consistent/know what your plan is then you have everything you need. The only thing left is mental toughness.
As for the quick snack... are you looking for carbs, protein, fats? Fruit and nuts are always easy. Granola bar.
I think the real problem with my focus is that I get about 6 hours of sleep. By the time I get home from school i'm dead. I'm always yawning at my workouts. I do need some fats for lunch, I'll try a baggie of nuts, unsalted peanuts sound good?
