It's easy to skip lunch, but it's the meal that can set you up for success for the rest of the afternoon. A salad and hearty soup combination or a wrap (check the calorie count though—it should hover around 500) will fill you up and keep you running at full power.
Snack
That feeling where you know you have to eat something fast, but you're not sure what? We call that snack stress, and it's to be avoided at all costs. That means always having a plan for what you're going to scarf down and thus not giving yourself the option to grab something random from the convenience store aisle. Throw a baggie of nuts or a snack bar (pick one that has less than 15 grams of sugar per serving!) in your backpack. And remember, you can never go wrong with raw veggies.