If I'm in a hurry, Greek yogurt and a banana (or apple). Protein shakes are great as well. I make mine with a tablespoon of both flax and chia seeds, a whole banana, low fat milk, and peanut butter (I only used a half scoop of the protein powder that my boyfriend buys, that stuff has A LOT go protein and calories). If there is time, scrambled egg whites with veggies ( usually onions and peppers), half of a bagel thin, and 1-2 slices of bacon. The real meal hold me over for a very long time. I'll admit that the busier I am, the less hungry I am and have made it through 14 hours without anything more than a breakfast shake and a banana without feeling hungry or tired. Not good for the blood glucose though, so I wouldn't recommend it.
Try eating some nuts, fruit, hard boiled egg, yogurt, or cheese if you get hungry before lunch. I know it's busy sometimes but grab a bite while you're charting if you don't have any other time. Something with protein and/or fiber will hold you over better than something heavy in simple carbs.